Midlands Astronomy Club Magazine
Sky Guide - Beginner’s targets for June
Issue 34- June, 2012
General notes Ahh, the summertime offers wonderful observing weather (and with it mosquitoes and every other kind of annoying insect so don't forget your bug-spray). While we don't get to observe until later in the evening, it sure is nice to be able to shed all those layers of clothing for some comfortable shorts and t-shirts‌ well OK then wet gear and wellies. There is a weak meteor shower this month, the June Lyrids, which peaks on the 15/16th of the month. Unfortunately the maximum rate observed is only about 8 per hour which is around the same intensity as the sporadic rate visible on any given night. Telescope Targets Many of the targets from April and May are still available for viewing in June. See the previous editions for their descriptions. T he N orther n H em is pher e 's premier globular cluster comes into good position this month. The Great Hercules Cluster (M13) is easily located by using 2 of the stars in the "keystone" of the constellation Hercules, namely Eta and Zeta Herculi. These are the 2 stars that form the top of the Keystone (the Western side). On line directly between these 2 and approximately a third of the way from Eta to Zeta is the cluster.
Above: A sky chart showing the centre of the Lyrid meteor shower. Look for the star Vega as a guide. Don't be afraid to try and use higher powers on this one. This cluster contains approximately a million stars and is over 100 light-years in diameter. It's located approximately 25,000 light-years from us and age estimates indicate that it is nearly 10 billion years old. Another globular cluster within the Hercules cluster is M92, while not as bright as it's more famous neighbour it's still a wonderful sight through any telescope. M92 forms an equilateral triangle with the top 2 stars in the Keystone (Zeta and Pi). M92 contains several hundred thousand stars approximately 100 light-years in diameter. It's located approximately 35,000 light-years away.
Club Notes Club Observing: The next club meets every 1st and 3rd Saturday of the month for our observing sessions held in the MAC grounds. If you wish to be informed of these sessions please email your name and mobile number to midlandsastronomy@gmail.com who will confirm if the session is going ahead (depending on weather).
MAC is a proud member of
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M13 was discovered by Edmond Halley in 1714, and catalogued by Charles Messier on June 1, 1764. It is estimated that M13 is about 145 light-years in diameter, and that it is composed of several hundred thousand stars. M13 was also aiming point of the first interstellar message known as the Arecibo message in 1974. This message was designed to communicate the existence of human life to hypothetical extra-terrestrials. The reason M13 was chosen was that with a higher star density, the chances of a life harbouring planet with intelligent life forms, were higher. That and the fact that is was well placed in the sky on the night in question.
Planets This month Mercury is visible as an evening object in the second half of the month and sets by around 23:15 in the evening.
The red planet (Mars) is visible as soon as darkness falls as is Saturn also. While Jupiter, Uranus and Neptune are all morning objects this month.
This month the big highlight is Venus which will transit the Sun on the morning of the 6th. On that morning sunrise is at around 04:50 and fourth contact when the planet slips off the sun’s disk occurs at 05:53. This gives a window of around 1 hour to see this event. This would be well worth observing as it is another 105 years to the next one! Never view the Sun directly with the naked eye or with any unfiltered optical device, such as binoculars or a telescope! Make sure you use proper solar filters to observe this safely.
General notes Check out www.heavensabove.com for the latest passes of the International Space Station and satellites, details of Space Shuttle launches and passes and for details of Iridium Flare activity. Clear skies and good hunting!
Latest Astronomy and Space News Kids Astronomy Quizzes and Games
By Kevin Daly http://members.aol.com/kdaly10475/index.html
Monthly Sky Guide Internet Highlights
Midlands Astronomy Club Magazine
Four White Dwarfs found eating Earthlike planets ................. 8 Going to the Moon? Don’t touch the historical artefacts ......... 8 Saturn’s Moon Titan ............................................................ 9 A Universe with billions of Binary Planets? ............................ 9
Kids Section Front cover image: This Star formation in the Tarantula Nebula is the largest, most violent region known in the whole Local Group of galaxies land lies in our neighbouring galaxy the Large Magellanic Cloud (LMC). Were the Tarantula Nebula at the distance of the Orion Nebula, a local star forming region, it would take up fully half the sky. The above image is one of the largest mosaics ever created by observations of the Hubble Space Telescope and has revealed unprecedented details of this enigmatic star forming region. The image was released to celebrate the 22nd anniversary of Hubble's launch.
Credit & Copyright: NASA, ESA, ESO, D. Lennon (ESA/STScI) et al., and the Hubble Heritage Team (STScI/AURA)
Kids Korner ....................................................................... 10
Quizzes and Games Exercise your brain ............................................................ 11
Monthly Sky Guide Beginners sky guide for this month .................................... 12
Internet Highlights Special content only available with the online version of the magazine ................................................................ 13
Hoy and Ho Tsung and Chang Hsi and Ho Chin and Hsi
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3. In what year did Galileo Galilei begin using the recently invented optical 9. In the year 14,000 telescope to observe the which star will be the heavens? pole star? 1604 Thuban 1608 Vega 1610 Polaris 1609 Sirius 4. What is the magnitude 10.In which vast area of the Sun from Earth? (50,000-100,000 A.U. in -25 extent) are most long-26.36 period comets believed -27.4 to originate? -26.72 Kuiper Belt 5. Which planet in our solar system is less dense than water which means that if all the planets were put into a huge ocean this planet would float? Uranus Jupiter Saturn Pluto
Schiaparelli Cloud Hubble Belt Oort Cloud
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Check your answers on this page. Answer 5: The correct answer was Saturn.
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8. How long is a mean tropical year? 365.256 366.012 365.687 365.242
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Answer 6: The correct answer was Io which is also extremely volcanically active due to the tidal forces exerted on it by Jupiter's tremendous gravitational pull.
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Answer 1: The correct answer was Mimas. Mimas is the smallest of Saturn's moons and is heavily cratered due to frequent impacts throughout history. The Herschel Crater, which is named after the astronomer William Herschel, is all that remains of the object that almost shattered the small moon and makes it look like the Death Star from Star Wars.
Superflares from Sun-like stars............................................. 6
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Answer 7: The correct answer was 365.256 days. A sidereal year is the time it takes the earth to complete one circuit around the sun. It is 20 minutes longer than a tropical year.
"Stellar Extremophiles" found where star formation isn't supposed to happen ..................................................... 5
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Answer 8: The correct answer was 365.242 days. A tropical year is the time measured from equinox to equinox. It is 20 minutes shorter than a sidereal year.
You can see more about the club and its events on www.midlandsastronomy.com or contact the club via e-mail at midlandsastronomy@gmail.com Meetings are informal and are aimed at a level to suit all ages.
Crowdsourcing the hunt for potentially dangerous Asteroids ............................................................................ 5
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Answer 2: The correct answer was Hsi and Ho. Back in the time of Hsi and Ho the Chinese believed that a solar eclipse was caused by a great dragon trying to eat the sun. They believed that creating a lot of noise would scare it away and when the eclipse of 2136 B.C. caught them off guard they thought it was just good fortune that the sun was not consumed by the monster.
M55 - Or a swarm of angry Bees? ........................................ 4
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Answer 9: The correct answer was Vega. This is due to precession and although it might look as if the stars in the night sky are fixed in space they are actually rotating around the galaxy as is our own sun.
Sifting through dust near Orion's Belt ................................... 4
SUDOKU
Answer 3: The correct answer was 1609. The first telescopes were invented by lens makers in the Netherlands in 1608 and within a year Galileo Galilei had turned them on the sky.
Your guide to the Transit of Venus ....................................... 3
1. Which moon of Saturn 6. Which of the four great Galilean moons around was almost shattered by Jupiter is the closest to the object that produced the planet? the Herschel Crater on its surface? Ganymede Iapetus Europa Mimas Callisto Titan Io Rhea 7. How long is Earth's sidereal year? 2. In 2136 B.C. the two Imperial Court 365.87 days astronomers in China 365.256 days were executed for not 365.242 days predicting a solar 364.987 days eclipse. Name them?
Answer 10: The correct answer was the Oort Cloud.
Latest Astronomy and Space News
All are welcome to attend. It also holds infrequent Observing Nights at its Observing Site in Clonminch, or at a member’s house (weather permitting) on the first Friday of every month..
Exercise your brain
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Answer 4: The correct answer was -26.72. The Sun is the brightest thing we see from Earth. In comparison the full moon is -13 and at it's brightest Venus is -4.4.
MAC meets on the first Tuesday of the month in the Presbyterian Hall, High Street, Tullamore from 8pm.
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Midlands Astronomy Club Magazine
Midlands Astronomy Club Magazine
Kid’s Korner How long does each phase of the moon last? What people sometimes call "moonlight" is really sunlight reflecting off the Moon's surface. The Moon itself puts out no light at all. It takes about four weeks for the Moon to orbit once around Earth. During this time, the Moon's position relative to Earth and the Sun is turn just a little tiny bit to your left, constantly changing. still holding the ball straight out. You will see only a thin lighted During part of its journey, the Moon crescent on the right side of the is between Earth and the Sun. Then, ball. Now turn to the left a little a few days later, it is off to one side. more until the light is on your right. Still later, the Moon moves around You will see half the lighted side of so that Earth is between it and the the ball. This position represents the First Quarter phase of the Sun. And so on. Moon. Now turn to the left again, Try this little demonstration. You will so the lamp is behind you. (If the need a lamp and a small ball (like a ball is directly in the shadow of tennis ball or a softball). If the lamp your head, raise the ball up a little has a shade, take it off. Pretend the higher.) You will see the entire lamp is the Sun, the ball is the lighted side of the ball. Now you Moon, and your head is Earth. Dark- are looking at the Full Moon. Now turn again so the lamp is on your en the room except for the lamp. left. Now you are looking at the Now, hold the ball straight out in Last Quarter phase. front of you. Stand facing the lamp. The ball will appear dark because The Moon's orbit actually dips a the lighted side of the ball is facing little bit above and below an away from you. T h i s imaginary line drawn between position represents the New Moon, Earth and the Sun. That is why dark and about to be born. Now, Earth seldom blocks the Sunlight
A diagram showing the phases of the moon. The inner circle shows the moon being highlighted by the sun and the outer circle shows how this reflection appears to us here on Earth.
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from reflecting off the full Moon. Once in a while, though, Earth does get directly in the way, and we have the exciting event called a lunar eclipse. This month, go outside each day or evening and observe the Moon moving through its phases. At night, look carefully, especially when the Moon is just a crescent, and find the dark part of the Moon. We can see the dark part because it reflects Earth light-that is, Sunlight reflected from Earth. So, how long does each phase of the Moon last? Well, the phases are just names we give to certain points along the Moon's smooth path around Earth. Technically, each phase, just like the one called a New Moon, when the Moon is exactly between Earth and the Sun, lasts only a brief instant. But to our eyes, a New Moon can last for a few days, representing the time that the Moon appears in the sky too near the Sun's position for us to see it at all. The time it takes the Moon to go through all its phases is about a month, and that was so important to our ancestors that they created the period of time we
Planets orbiting the Sun inside Earth's orbit show phases as in this drawing. When the other planet is nearest Earth (called inferior conjunction) it appears in its "new" phase. When farthest from Earth on the other side of the Sun (called super- ior conjunction), it is in its "full" phase and visible only around sunset or sunrise.
Your guide to the Transit of Venus
Venus in its gibbous phase, photographed by the Galileo spacecraft. call a month. Maybe you've even noticed that the word month is like the word moon. It isn't just the Moon that appears to have phases. The planets also have phases. For example, the orbit of Venus is inside the orbit of Earth. When Venus is in the part of its orbit between Earth and the Sun, we can't even see it, because its sunlit side will be away from us. This position is similar to the New Moon phase. As Venus progresses around the Sun, more and more of its illuminated side is visible to us on Earth. When Venus is on the far side of the Sun, we will see its Full Phase. At this time, we will see Venus only around sunset or sunrise, when the sky is just dark enough to see it even though Venus appears in the sky near the Sun.
On June 5-6 you get your last chance to see one of the rarest of astronomical events, the Transit of Venus, during which the black disk of Venus passes across the glowing disk of the Sun. This transit has happened just seven times since the invention of the telescope more than 400 years ago. The last transit was in 2004. There won’t be another until December 2117. Here’s how and where to see next month’s transit for yourself… Where To See The Transit The maps below shows where the 2012 transit of Venus is visible…
Even Earth has phases, as viewed from the Moon. Photos taken of Earth by Apollo astronauts show part of Earth in darkness and part lit by the Sun.
The western and central Pacific, including most of Australia, New Zealand, Fiji, and Hawaii can see the entire transit. Western and southern Africa, Spain and Portugal, and eastern South America will not see the transit at all because it occurs when the sun has set. And the rest of the world can see some of the transit after the Sun rises or before it sets. Here in Ireland we will only get to see the last 47 minutes of the transit.
Planets orbiting the Sun outside Earth's orbit show phases as in this drawing. When Earth is positioned on a line between the Sun and the other planet called opposition), the planet is in its full phase and shines brightly in Earth's night sky. When farthest from Earth on the other side of the Sun called conjunction), the other planet also appears full, but is visible only around sunset or sunrise.
Why It Happens Like a solar eclipse, a transit occurs when Venus, rather than the Moon, passes between Earth and the Sun. And like a solar eclipse, the transit requires careful alignment of the Sun, Earth, and Venus. As seen from Earth, Venus usually passes over or under the Sun every 584 days, on average. But the geometry and periods of the orbits of two planets cause Venus to pass in front of the Sun at well-defined intervals of 121.5 and 101.5 years in either June or December. And the transits occur in pairs separated by eight years. The last transit occurred on June 8, 2004. The last pair of transits were on December 1874 and December 1882.
The Transit of Venus once held the key to understanding the size of the solar system. In the early 18th century, Edmund Halley determined a way to measure the distance from the Earth to the Sun by precisely timing the transit of Venus from widely separated parts of the Earth. Once this distance was known, the distances to other planets could be determined through Kepler’s Laws. These transits were so important that most advanced nations sent astronomers around to world to measure the events of 1761 and 1769. The transit of Venus in 1761 yielded few conclusive results despite hundreds of attempted measurements. But the transit of 1769 was measured precisely by, among others, the team led by Lieutenant James Cook, RN, who witnessed the event from Tahiti before sailing on to claim Australia for England. Astronomers used Cook’s measurements to calculate a distance to the Earth of 150 million kilometres, close to the nowaccepted value of 149,597,870.7 kilometres. How To See The Transit For this June 5-6 transit, Venus will traverse the northern half of the Sun’s disk. You’ll get the best view of the transit with a telescope, but a telescope is not required. Telescope or not, you’ll need a safe solar filter. Here’s some advice on finding a solar filter suitable for observing this event. If you don’t have your own filter, check if your local astronomy club is holding a public event during the transit.
Above: On June 8, 2004, a rare celestial event the Venus transit, the apparent crossing of our planetary neighbour in front of the sun was captured from the unique perspective of NASA's sun-observing TRACE spacecraft. The top image shows Venus on the eastern limb of the sun. The bottom left image is in the ultraviolet, and the bottom right image is in the extreme ultraviolet. The last V " enus transit"occurred more than a century ago, in 1882, and was used to compute the distance between Earth and the sun. Scientists with NASA's Kepler mission hope to discover Earth-like planets orbiting other stars by searching for transits similar to this one. If people miss this months transit there will not be another one until Dec. 11, 2117. They’ll have properly equipped scopes and other hardware to help you enjoy this rare event. The transit of Venus unfolds in four stages. First, the leading edge of the planet contacts the Sun. Then the trailing edge makes contact, which is hard to time exactly because of the “black drop effect” that bleeds darkness from the limb of the planet as it moves onto the solar disk. The same two stages reverse themselves as the planet leaves the solar disk. The June 5-6, 2012 transit takes about 6 hours, which is a long time compared to the scant few minutes of a solar eclipse.
fact, uses this same idea… a transiting planet blocking light from its home star… to look for Earth-like planets around nearby stars. Astronomers will use the 2012 transit of Venus to test new measurement techniques to find extra-solar planets using spacebased telescopes. The history and the rarity and the beauty of this event make it a compelling and memorable sight. Please… observe it for yourself if you can. www.oneminuteastronomer.com
During the transit, the black disk of Venus, just 33x smaller than the solar disk, blocks enough light to measurably decrease t he Sun’s brightness. NASA’s Kepler observatory, in
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Midlands Astronomy Club Magazine
Sifting through dust near Orion's Belt Dust is important to astronomers as dense clouds of gas and dust are the birthplaces of new stars. A new image of the region surrounding the reflection nebula Messier 78, just to the north of Orion’s Belt, shows clouds of cosmic dust threaded through the nebula like a string of pearls. The observations, made with the Atacama Pathfinder Experiment (APEX) telescope, use the heat glow of interstellar dust grains to show astronomers where new stars are being formed.
APEX observations are overlaid on the visible-light image in orange. Sensitive to longer wavelengths, they reveal the gentle glow of dense cold clumps of dust, some of which are even colder than – 418 Fahrenheit (–250º Celsius). In visible light, this dust is dark and obscuring, which is why telescopes such as APEX are so important for studying the dusty clouds in which stars are born.
Dust may sound boring and uninteresting, but this new image of Messier 78 and surroundings, which reveals the submillimeterwavelength radiation from dust grains in space, shows that dust can be dazzling. Dust is important to astronomers as dense clouds of gas and dust are the birthplaces of new stars.
One filament seen by APEX appears in visible light as a dark lane of dust cutting across Messier 78. This tells us that the dense dust lies in front of the reflection nebula, blocking its bluish light. Another prominent region of glowing dust seen by APEX overlaps with the visible light from Messier 78 at its lower edge. The lack of a corresponding dark dust lane in the visible light image tells us that this dense region of dust must lie behind the reflection nebula.
In the center of the image is Messier 78 (NGC 2068). When seen in visible light, this region is a reflection nebula, meaning that we see the pale blue glow of starlight reflected from clouds of dust. The
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Midlands Astronomy Club Magazine
clouds reveal gas flowing at a high velocity out of some of the de nse clumps. These outflows are ejected from young stars while the star is still forming from the surrounding cloud. Their presence is therefore evidence that these clumps are actively forming stars. At the top of the image is another reflection nebula, NGC 2071. While the lower regions in this image contain only low-mass young stars, NGC 2071 contains a more massive young star with an estimated mass five times that of the Sun, located in the brightest peak seen in the APEX observations. www.astronomy.com
Saturn’s Moon Titan Even casual observers are gobsmacked by a first glimpse of the rings of Saturn. But keen-eyed beginners will notice a prominent orange “star” near Saturn which follows the planet from night to night. This is no star… it’s Saturn’s largest moon, Titan, one of the largest moons in the solar system and the only moon with a thick atmosphere… By far the largest of Saturn’s moons, Titan makes up nearly 96% of the mass of all bodies orbiting Saturn, including the rings. Titan ranks as the second-largest moon in the solar system after Jupiter’s Ganymede, with twice the mass of Earths’ moon. Titan is larger than the planet Mercury.
Above: This image of the region surrounding the reflection nebula Messier 78, just to the north of Orion’s belt, shows clouds of cosmic dust threaded through the nebula like a string of pearls. The submillimeter-wavelength observations, made with the Atacama Pathfinder Experiment (APEX) telescope and shown here in orange, use the heat glow of interstellar dust grains to show astronomers where new stars are being formed. They are overlaid on a view of the region in visible light. M55 is part of the Messier catalogue; a collection of objects that looked comet-like to the eyes of Charles Messier, a French astronomer working in the 18th century. Messier recorded a list of more than 100 objects which could be confused as comets: galaxies, clusters, and nebulae.
M55 - Or a swarm of angry Bees? Globular clusters are my absolute favourite telescope targets. Okay, Saturn, and then globular clusters. And that’s why I’ve absolutely fallen in love with this amazing picture from the European Southern Observatory of the globular cluster M55, located in the constellation Sagittarius. Globular clusters are my absolute favourite telescope targets. Okay, Saturn, and then globular clusters. And that’s why I’ve absolutely fallen in love with this amazing picture of the globular cluster M55, located in the constellation Sagittarius. Globular clusters contain vast numbers of stars clumped together in a tight area. In the case of M55, there are about 100,000 stars grouped up within a sphere only 100 light-years across. Astronomers know that globular clusters are old, almost as old as the Universe itself.
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M55 is thought to have formed 12.3 billion years ago. The most ancient stars in the cluster burned out a long time ago, detonating as supernovae. We’re now left with the cooler, lower mass stars, which slowly wink out one-by-one becoming white dwarfs. Our own Sun is only halfway through its own lifespan, before it runs out of hydrogen fuel and becomes a white dwarf. There are at least 160 globular clusters scattered across the Milky Way, grouped up more towards
our galaxy’s core. We can only see some of the clusters because the bright core of the Milky Way obscures our view to objects on the other side. But other galaxies, with their own globular clusters show us what our own galaxy probably looks like from afar.
To see M55 on your own you’ll need at least a pair of 50 mm binoculars or a small telescope, some nice dark skies, and a clear view to the constellation Sagittarius. Sagittarius looks exactly like a teapot in the sky, hovering above the southern horizon in summer. www.universetoday.com
Saturn’s rings. You can see this big moon with binoculars, while the rings are visible only in telescopes. In a larger scope, some observers can even resolve Titan into a tiny orange disk… a tantalizing glimpse of this distant, icy world. While Titan is the biggest of Saturn’s satellites, the planet has some 62 moons with confirmed orbits. Of this large collection, nine were discovered with telescopes before the age of spaceflight. They are, in increasing distance from Saturn: Mimas, Enceladus, Tethys, Dione, Rhea, Titan, Hyperion, Iapetus, and Phoebe. The moons were named after the Titans of ancient Greek legend.
Titan is also the only Moon with a substantial atmosphere, which is made mostly of nitrogen along with traces of methane and other organic molecules. Titan has lakes of liquid hydrocarbons and hills and dunes and boulders of frozen water (see image above). The presence of organic molecules suggests Titan may have the right chemistry for simple forms of life to develop, so planetary scientists intensely study With a 6″ or 8″ telescope, you can this massive moon. see as many as five of Saturn’s moons– Titan, Enceladus, Dione, For us backyard observers, Titan Tethys, and Rhea. The moons presents an easier target than move from night to night, much
tan as largest moon Ti Saturn and its all telescope. sm a in ar pe it might ap
like Jupiter’s moons, so they are tricky to track. Sky & Telescope publishes a free Javascript utility to help you sort out which moon is which. You can find it here: http://www.skyandtelescope.com/ o b s e r v i ng / o b j e c ts / j a va s c r i p t / saturn_moons# www.oneminuteastronomer.com
A Universe with billions of Binary Planets? The discovery that there are perhaps billions of solo rogue planets and binary planet systems in the Milky Way alone has led to a new theoretical study by astronomer Hagai Perets and his colleague at the Harvard-Smithsonian Centre for Astrophysics that proposes a possible answer: the distant planets are not part of the original stellar system - they were captured by the star. Astronomers know that there are many so-called "free floating planets" in space - planets that have been tossed out of their original solar system by a random gravitational encounter with another planet. Some of these orphan planets have recently been detected.
nearby to interfere with the "adoption." They ran a series of computer simulations to test all these and other possibilities, and they found not only that such a capture was possible, but that a star could even capture several orphan planets.
The CfA team calculated that it would be possible for a star to capture one of these orphans if the conditions were right; namely, if the star and planet happen to pass close to each other with only a small velocity difference, and if there are no other massive bodies
In fact, they found that sometimes two free floating planets could capture one another and form a binary planet. None of these binaries has yet been seen, although some
astronomers think that since Pluto and its moon Charon have such similar masses they are a binary system, although not necessarily one that was captured. The new results seem to offer a reasonable, if exotic, explanation for some of the complex planetary configurations that have been discovered, and they remind us that nature is full of surprises. www.dailygalaxy.com
To help find your way around the night sky, Skymaps.com makes available for free each month a map of the night sky. The Evening Sky Map is suitable for all stargazers including newcomers to astronomy and will help you to:
• Identify planets, stars and major constellations.
• Find sparkling star clusters, wispy nebulae & distant galaxies.
• Locate and follow bright comets across the sky.
• Learn about the night sky and astronomy.
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Midlands Astronomy Club Magazine
Midlands Astronomy Club Magazine
Crowdsourcing the hunt for potentially dangerous Asteroids
Four White Dwarfs found eating Earthlike planets It's no fairy tale: Four hungry white dwarfs have been found "snacking" on the shattered remains of Earthlike planets, according to a new study. The findings foreshadow what might happen to our solar system when the sun dies in about five billion years, astronomers say. As stars like our sun run out of nuclear fuel, they swell, becoming red giants. Astronomers think that when this happens to our star, its bulging atmosphere will engulf Mercury, Venus, and maybe even Earth. Eventually, the outer layers of a sunlike star's atmosphere will balloon away to form a nebula, leaving the star's dense core—a white dwarf—shining in the centre. The study authors speculate that any planets not roasted by the star's initial expansion—which takes tens to a few hundred million years— would have their orbits destabilized as the dying star loses mass. The changing orbits would sometimes lead to planets crashing into each other, churning up chunks of rocky debris. Eventually some of these planetary pieces could be nudged so close to the white dwarf that they'd fall into the star and get ripped apart. Evidence for this theory seems to lie in the newly observed white dwarfs' atmospheres, said study leader
Boris Gänsicke, an astrophysicist at the University of Warwick. Normally, a white dwarf' s atmosphere is a mix of only hydrogen and helium, relatively light elements. That's because a white dwarf's intense gravity pulls heavier elements toward the star's core. Any other chemicals in a white dwarf's atmosphere must therefore come from debris falling onto the star's surface. To hunt for signs of planetary consumption, Gänsicke and colleagues looked at 80 white dwarf stars in ultraviolet using the NASA/ESA Hubble Space Telescope. The team found four stars whose atmospheres contain oxygen, magnesium, iron, silicon, and a small bit of carbon—just the elements expected if the stars are absorbing dust from former planets. "The abundances we find are almost exactly the same as those of the entire Earth," Gänsicke said.
Going to the Moon? Don’t touch the historical artefacts Don’t say you haven’t been warned. NASA put out an official document specifying how close any future spacecraft and astronauts visiting the Moon can come to the artefacts left on the lunar surface by all US space missions, including the Apollo landing sites, robotic landing sites and impact sites like LCROSS. While these recommendations are not mandatory (there’s obviously no way to enforce this yet) the document states, “rather, it is offered to inform lunar spacecraft mission planners interested in helping preserve and protect lunar historic artefacts and potential science opportunities for future missions.”
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What’s the best way to look for potentially hazardous asteroids? Get as many eyes on the sky as you can. That’s the impetus behind a new partnership between the European Space Agency and the Faulkes Telescope Project, which will encourage amateur astronomers to look for asteroids, as well as providing educational opportunities that will allow students to discover potentially dangerous space rocks, too.
Planets shift their orbits and collid e as they circle a dy ing star in an artist's conceptio n.
"If you could shred the Earth into dust and put it into the white dwarf, it would match the chemical composition." In addition, one star, called PG0843+516, is even more heavily iron-enriched than the other dwarfs and contains high abundances of nickel and sulphur. This makes sense if the star is devouring a chunk of planetary core, the study authors say. "If you think about what the Earth looks like inside, it is almost pure iron and nickel. What we imagine is we see bits of a body that was at some point large enough to have an iron core. The dust seen surrounding the four white dwarfs will be eaten up within "maybe a they want to make sure nothing from previous missions is disturbed. NASA said in an accompanying press release that they recognize the steadily increasing technical c a pa b ilities of s pa ce -far ing commercial entities and nations throughout the world that may be on the verge of landing spacecraft on the surface of the Moon.
For example, NASA recommends an artefact boundary extending 75 m from the Apollo 11 lunar module descent stage.
The document specifies how close another spacecraft can hover, flyover, hop or touchdown near landing sites or spacecraft.
NASA isn’t expecting a rush of astro-looters to descend upon the Moon, but with China discussing a Moon landing, and with several Google Lunar X PRIZE teams hoping to send robotic landers,
And not just hardware is included in the “don’t touch” areas: “U.S. human, human-robotic lunar presence, including footprints, rover tracks, etc., although not all anthropogenic indicators are
few thousand or tens of thousands of years but at some point, another planetary fragment could fall toward the star, creating more of these telltale rocky crumbs," he said. However, the scientists can't tell how many fragments—or even whole planets—might remain around the currently feeding white dwarfs. "We know from studies of other planetary systems that systems come in all kinds of shapes. If there are more lingering worlds orbiting the four white dwarfs, "we don't know [what] the other rocky planets look like and how many there could be, or how stable or unstable their orbits are." www.nationalgeographic.com
protected as identified in the recommendations,” the document says. NASA’s decisions on proximity boundaries were made from recommendations from external experts from the historic, scientific and flight-planning communities and apply to US government artefacts on the lunar surface. NASA says they released this document to open discussions with commercial and international space agencies, and seek any improvements to the recommendations. www.universetoday.com
ESA’s Space Situational Awareness (SSA) program is part of an international effort to be on the lookout for space hazards – not only asteroids but disruptive space weather and space debris objects in Earth orbit.
of Glamorgan in the UK. The project has been active in public education and science outreach, and is a partner of the US-based Las Cumbres Observatory Global Telescope network, which owns and operates two telescopes. Faulkes supports hundreds of But asteroids pose a problem. schools across Europe, offering Often, they are hard to see because free access to their online they can be very dark, they can observing program to schools. approach rather too close before anyone sees them, and they’re The Faulkes project has two often spotted only once and then telescopes where you can sign up disappear before the discovery can for observing online: Haleakala, be confirmed. Hawaii and Siding Spring, Australia. That’s where crowdsourcing comes in, to get more eyes on the skies. “Our new cooperation with ESA is ESA is turning to schools and a great opportunity. Use of the 2 amateur astronomers to help as m-diameter telescopes in Hawaii part of Europe’s contribution to the global asteroid hunt.
and Siding Spring, Australia, will greatly enhance asteroidspotting for the SSA programme, enabling fainter object detection and tracking from a global telescope network,” says Nick Howes, Pro-Am Program Manager at the Faulkes Telescope. “For European students, collaborating on exciting ESA activities and possibly detecting new NEOs is very appealing, as its engagement with one of the world’s great space agencies doing critical scientific work.” While the Faulkes Above: An image of the Faulkes Telescope in project focuses on Hawaii. schools, amateurs will be able to freely access the data archives. ESA’s amateur astronomers have identified archives are also open to all, and hundreds of asteroid candidates, over t h e y w o r k w i t h a m a t e u r 20 of which have been confirmed and astronomers with the Teide named. Find out more about how Observatory Tenerife Asteroid where students in schools across the Survey (TOTAS) team, who use a 1 UK/EIRE and some European -meter telescope at the ESA’s locations can sign up here: Optical Ground Station on Tenerife in the Canary Islands. Since http://www.faulkes-telescope.com/ starting their SSA-sponsored survey www.universetoday.com work in January 2010, the TOTAS
"Stellar Extremophiles" found where star formation isn't supposed to happen
This month, the UK’s Faulkes Telescope Project will become the latest team to formally support the SSA program. Spain’s La Sagra Sky Survey, operated by the Observatorio Astronomico de Mallorca, began helping SSA earlier "We’re finding stars in extreme galactic environments where star this year. formation isn't supposed to “The wider astronomy community happen," explains NASA GALEX offers a wealth of expertise and project scientist Susan Neff. “This enthusiasm, and they have the time is a very surprising development." and patience to verify new sightings; this helps tremendously,” An intriguing double circumnuclear says Detlef Koschny, Head of NEO ring has been discovered at the activity at ESA’s SSA program centre of M83. GALEX, which office. “In return, we share stands for “Galaxy Evolution observing time at ESA’s own Optical Explorer,” is an ultraviolet space Ground Station in Tenerife and telescope with a special ability: It provide advice, support and is super-sensitive to the kind of UV professional validation. We’ll assist rays emitted by the youngest stars. This means the observatory can them in any way we can.” detect stars being born at very The Faulkes Telescope Project runs great distances from Earth, more both educational and research than halfway across the Universe. programs, based at the University The observatory was launched in
2003 on a mission to study how galaxies change and evolve as new stars coalesce inside them. "In some GALEX images, we see stars forming outside of galaxiesin places where we thought the gas density would be too low for star birth to occur," says GALEX team member Don Neil. Stars are born when interstellar clouds of gas collapse and contract under the pull of their own gravity. If a cloud gets dense and hot enough as it collapses, nuclear fusion will kick in and voila! a star is born. The spiral arms of the Milky Way are a "goldilocks zone" for this process. "Here in the Milky Way we have plenty of gas. It’s a cosy
place for stars to form," says Neil. But when GALEX looks at other more distant spiral galaxies, it sees stars forming far outside the gassy spiral disk. The observatory has also found stars being born: in elliptical and irregular galaxies thought to be gaspoor (e.g., 1, 2); in the gaseous debris of colliding galaxies (1, 2); in vast "comet-like" tails that trail behind some fast-moving galaxies (1, 2); in cold primordial gas clouds, which are small and barely massive enough to hang together. According to GALEX, stellar extremophiles populate just about every nook and cranny of the cosmos where a wisp of gas can get together to make a new sun. “This could be telling us something profound about the star-forming process, there could be ways to make stars in extreme environments that we haven’t even thought of yet.” www.dailygalaxy.com
www.midlandsastronomy.com Page - 5
Midlands Astronomy Club Magazine
Midlands Astronomy Club Magazine
Are we alone?
Superflares from Sun-like stars
Have you ever looked up at the night sky and wondered are we alone? Well our Chairman Declan Molloy has, here are his thoughts on the subject of alien life in the universe.
NASA's Kepler mission is finding solar-type stars that emit jawdropping explosions of high-energy particles and radiation. Now astronomers are looking into why some solar-type stars emit superflares — and why the Sun never will. In 1859 the Sun emitted the most powerful flare in recorded history, the so-called Carrington event. Energetic particles danced off telegraph lines, creating sparks that shocked operators and ignited fires in telegraph paper. Brilliant aurora were seen as far south as the Caribbean. Estimates are rough, but this flare probably produced some 1025 Joules of energy — a million times more than is stored in the world’s entire nuclear arsenal.
searched eight months of data from 2009, when Kepler monitored 83,000 stars of the same type as the Sun. Only 148 solar-type stars (0.2%) emitted a superflare under Kepler’s watchful eye, so the events must be exceedingly rare. But every superflaring star had one thing in common: gigantic starspots. As the starspots formed and dissolved on the surface of the star, the star’s brightness varied in a quasi-periodic way. Starspots harbour magnetic energy that can But in the grand scheme of things, be released when magnetic fields that’s nothing so-called “superflares” tangle and reconnect, flinging can be 10,000 times more powerful. plasma off the surface of the star. And, it turns out, regular, ol’ solartype stars are perfectly capable of Superflaring stars also tend to releasing these massive belches of rotate quickly. It was found that energy. New results from NASA’s stars with shorter rotation periods Kepler mission have found 365 had more superflares, presumably superflares coming from solar-type because magnetic activity arises stars, suggesting that superflares from the interaction between a might not be so uncommon in star’s rotation and the boiling “normal” stars. motion of its ionized gas. But slowly rotating stars are still capable of producing flares, just not as often. Of the 365 superflares found, 14 came from solar-type stars with rotation periods similar to the Sun’s. Extrapolating from the superflares seen, the number of stars observed, and the length of time that Kepler watched them, the scientists found that a superflare of 1027 Joules should occur every 800 years, and one of 1028 Joules every 5,000 years. Above: An artist illustrates the giant starspots (dark regions) that produce superflares (white region). These starspots dwarf those seen on the visible surface of the Sun. Dozens of superflares from solartype stars have been seen before, but observations have been sporadic at best. Kepler, famous for its exoplanet search, makes the study of these rare events feasible in a systematic way. Hiroyuki Maehara and his colleagues
www.midlandsastronomy.com Page - 6
Yet, in 2,000 years of geophysical records, the Sun has never issued such a violent event. Spots on the Sun never get so big that they’re in danger of emitting a superflare. And that’s a good thing too. The strongest superflare found by Maehara would send high-energy particles “knocking around Earth's atmosphere, disassociating the nitrogen and oxygen, getting rid of the entire ozone layer”. In addition to superquick sunburns and a collapsing food chain, a superflare
A normal star emits a superflare thousands of times as bright as typical solar flares in this artist's illustration. could fry the electric grid and down the whole satellite system, he adds. What Sets Superflaring Stars Apart? One long-standing theory holds that “hot Jupiters,” Jupiter-sized planets that circle their host star in dizzyingly close orbits, affect a star’s magnetic activity. The planet acts as an anchor for the star’s magnetic field, Schaefer explains. As the planet orbits the star, the magnetic field lines connecting the two twist and stretch like rubber bands until sooner or later they snap. “When a rubberband breaks it will snap back, and we'll feel the snap and hear the pop.” In the case of magnetic fields, a field line snapping back to the star will use some of its energy to accelerate particles, and some to emit light in every wavelength from radio to Xray.
in solar-type stars, then about 15 hot-Jupiter transits should have been detected around superflaring stars. But that doesn’t mean the hotplanet theory is kaput, only that it’s in need of revision. “Smaller planets could easily hide and be rare in the Kepler data,” Schaefer suggests. “The magnetic field can be anchored in any planet with a magnetic field, say a superearth or an earth, and the physics would all be the same.” As Kepler continues monitoring solar -type stars the ever-climbing mountain of data will help astronomers understand what makes a superflare. Plus, astronomers could soon get some help. Schaefer suggests that looking for more flares could make a perfect citizen science project. In the nottoo-distant future, the answers might lie in the hands of the public. www.skyandtelescope.com
The hot-Jupiter theory makes good physical sense, and there are no really good alternatives at the moment. So imagine the researcher’s surprise when, of a l l t h e superflaring stars obser ved by Kepler, none had a hot Jupiter associated with it. If these were really behind unusual activity
Above: NASA's Solar Dynamic Observatory images a solar flare as it spits ionized gas off the Sun’s surface.
How many of us have looked upwards and wondered if we are alone, I have and as a young teenager I avidly soaked up every available book on the topic. Eason Bookshop on a Saturday morning would be raided for the latest book on flying saucers with lurid accounts of alien abduction and unexplained happenings in America and Europe with the occasional sighting in the USSR. My brain was like a wad of paper kitchen towel – it would soak up facts and figures. I had a map of the world on my bedroom wall and with little flags fashioned from dress pins and red insulating tape I would diligently plot the position of all the sighting in order to discover a pattern… there had to be a pattern.
Sorry to be so negative but when asked last year during a radio interview whether I thought there was aliens visiting earth my answer was: Elephants exist, we have their DNA, we have photographic evidence of elephants in the wild, in zoo’s we have their tusks fashioned into chess pieces – we have a pile of elephant evidence (metaphorically speaking) but the laboratory display cabinets stand empty when it comes to alien artefacts. Anyone who says anything different it’s only wishful The simple inescapable facts are: thinking and self delusion. no alien craft has landed on the But hang on there just a moment – Whitehouse lawn or impaled itself hold your horses Declan, are you on the Dublin Spire because the saying that we are alone in the great ocean of space is so vast that universe? …NO… I’m not. Imagine earth is infinitely smaller than a Frank Drakes equation is a little bit bottle cork bobbing on the great Indeed there was, it was a pattern correct; let’s say there is a handful Pacific Ocean. of western culture and what I later of sentient aliens out there – with describe as paradise syndrome. an evolved curiosity – then surely An analogy I use quite often is – Less well off cultures have little or they would seek us out. Surely one imagine the earth covered from no time for the Hollywood alien or or two of them would have horizon to horizon with thick his sinister agenda to be bothered – technologies smarter than ours and woodland and you dropped 300 but this I learned in hindsight. would go exploring and eventually people at random on the Despite the reported sightings there pick up signs of our existence (our surface...what would the chances is zero evidence for alien visitation. radio broadcast for example). Well, be of any two individuals running There are no crashed spacecraft, maybe’s if’s and buts’ and if my into each other within a single life no alien autopsies and no auntie was somewhat differently time. conspiracy. built she would be my uncle. When we think of alien – think alien life or life not native to our earth. You need to widen the definition and be prepared to encounter something a little less complex than Mr Spock from the planet Vulcan… no, Ladies and gentlemen may I introduce to you Slime On Rock (if we are lucky) – more likely simple b a c t e r i a . Remember, for nearly three quarters of the history of life on earth – it was microbial, smaller than the eye can see. And consider this nearly 95% of all life on earth now is Above: Image copyright of http://xkcd.com
smaller than the eye can see. Higher forms of life are possible but probably rare; there is every reason to expect that other planets will have had a roll of the evolutionary dice as well as us, that simple molecules will by chance randomly create a simple cell and by random chemistry a replicator – something that can reproduce. Maybe it happens quite often, more likely it is quite rare – but only needs to happen once! And bingo the clock is ticking – So by all means keep watching the skies but wrap up warm and enjoy the majesty of the heavens, enjoy what is, and dream of what might be.
Declan Molloy is the Ch ai rm an of th e Midlands Astronomy Club (MAC) having been a member for many years. Declan is also enjoys painting and sketching and has painted a number of astronomical objects.
www.midlandsastronomy.com Page - 7
Midlands Astronomy Club Magazine
Midlands Astronomy Club Magazine
Are we alone?
Superflares from Sun-like stars
Have you ever looked up at the night sky and wondered are we alone? Well our Chairman Declan Molloy has, here are his thoughts on the subject of alien life in the universe.
NASA's Kepler mission is finding solar-type stars that emit jawdropping explosions of high-energy particles and radiation. Now astronomers are looking into why some solar-type stars emit superflares — and why the Sun never will. In 1859 the Sun emitted the most powerful flare in recorded history, the so-called Carrington event. Energetic particles danced off telegraph lines, creating sparks that shocked operators and ignited fires in telegraph paper. Brilliant aurora were seen as far south as the Caribbean. Estimates are rough, but this flare probably produced some 1025 Joules of energy — a million times more than is stored in the world’s entire nuclear arsenal.
searched eight months of data from 2009, when Kepler monitored 83,000 stars of the same type as the Sun. Only 148 solar-type stars (0.2%) emitted a superflare under Kepler’s watchful eye, so the events must be exceedingly rare. But every superflaring star had one thing in common: gigantic starspots. As the starspots formed and dissolved on the surface of the star, the star’s brightness varied in a quasi-periodic way. Starspots harbour magnetic energy that can But in the grand scheme of things, be released when magnetic fields that’s nothing so-called “superflares” tangle and reconnect, flinging can be 10,000 times more powerful. plasma off the surface of the star. And, it turns out, regular, ol’ solartype stars are perfectly capable of Superflaring stars also tend to releasing these massive belches of rotate quickly. It was found that energy. New results from NASA’s stars with shorter rotation periods Kepler mission have found 365 had more superflares, presumably superflares coming from solar-type because magnetic activity arises stars, suggesting that superflares from the interaction between a might not be so uncommon in star’s rotation and the boiling “normal” stars. motion of its ionized gas. But slowly rotating stars are still capable of producing flares, just not as often. Of the 365 superflares found, 14 came from solar-type stars with rotation periods similar to the Sun’s. Extrapolating from the superflares seen, the number of stars observed, and the length of time that Kepler watched them, the scientists found that a superflare of 1027 Joules should occur every 800 years, and one of 1028 Joules every 5,000 years. Above: An artist illustrates the giant starspots (dark regions) that produce superflares (white region). These starspots dwarf those seen on the visible surface of the Sun. Dozens of superflares from solartype stars have been seen before, but observations have been sporadic at best. Kepler, famous for its exoplanet search, makes the study of these rare events feasible in a systematic way. Hiroyuki Maehara and his colleagues
www.midlandsastronomy.com Page - 6
Yet, in 2,000 years of geophysical records, the Sun has never issued such a violent event. Spots on the Sun never get so big that they’re in danger of emitting a superflare. And that’s a good thing too. The strongest superflare found by Maehara would send high-energy particles “knocking around Earth's atmosphere, disassociating the nitrogen and oxygen, getting rid of the entire ozone layer”. In addition to superquick sunburns and a collapsing food chain, a superflare
A normal star emits a superflare thousands of times as bright as typical solar flares in this artist's illustration. could fry the electric grid and down the whole satellite system, he adds. What Sets Superflaring Stars Apart? One long-standing theory holds that “hot Jupiters,” Jupiter-sized planets that circle their host star in dizzyingly close orbits, affect a star’s magnetic activity. The planet acts as an anchor for the star’s magnetic field, Schaefer explains. As the planet orbits the star, the magnetic field lines connecting the two twist and stretch like rubber bands until sooner or later they snap. “When a rubberband breaks it will snap back, and we'll feel the snap and hear the pop.” In the case of magnetic fields, a field line snapping back to the star will use some of its energy to accelerate particles, and some to emit light in every wavelength from radio to Xray.
in solar-type stars, then about 15 hot-Jupiter transits should have been detected around superflaring stars. But that doesn’t mean the hotplanet theory is kaput, only that it’s in need of revision. “Smaller planets could easily hide and be rare in the Kepler data,” Schaefer suggests. “The magnetic field can be anchored in any planet with a magnetic field, say a superearth or an earth, and the physics would all be the same.” As Kepler continues monitoring solar -type stars the ever-climbing mountain of data will help astronomers understand what makes a superflare. Plus, astronomers could soon get some help. Schaefer suggests that looking for more flares could make a perfect citizen science project. In the nottoo-distant future, the answers might lie in the hands of the public. www.skyandtelescope.com
The hot-Jupiter theory makes good physical sense, and there are no really good alternatives at the moment. So imagine the researcher’s surprise when, of a l l t h e superflaring stars obser ved by Kepler, none had a hot Jupiter associated with it. If these were really behind unusual activity
Above: NASA's Solar Dynamic Observatory images a solar flare as it spits ionized gas off the Sun’s surface.
How many of us have looked upwards and wondered if we are alone, I have and as a young teenager I avidly soaked up every available book on the topic. Eason Bookshop on a Saturday morning would be raided for the latest book on flying saucers with lurid accounts of alien abduction and unexplained happenings in America and Europe with the occasional sighting in the USSR. My brain was like a wad of paper kitchen towel – it would soak up facts and figures. I had a map of the world on my bedroom wall and with little flags fashioned from dress pins and red insulating tape I would diligently plot the position of all the sighting in order to discover a pattern… there had to be a pattern.
Sorry to be so negative but when asked last year during a radio interview whether I thought there was aliens visiting earth my answer was: Elephants exist, we have their DNA, we have photographic evidence of elephants in the wild, in zoo’s we have their tusks fashioned into chess pieces – we have a pile of elephant evidence (metaphorically speaking) but the laboratory display cabinets stand empty when it comes to alien artefacts. Anyone who says anything different it’s only wishful The simple inescapable facts are: thinking and self delusion. no alien craft has landed on the But hang on there just a moment – Whitehouse lawn or impaled itself hold your horses Declan, are you on the Dublin Spire because the saying that we are alone in the great ocean of space is so vast that universe? …NO… I’m not. Imagine earth is infinitely smaller than a Frank Drakes equation is a little bit bottle cork bobbing on the great Indeed there was, it was a pattern correct; let’s say there is a handful Pacific Ocean. of western culture and what I later of sentient aliens out there – with describe as paradise syndrome. an evolved curiosity – then surely An analogy I use quite often is – Less well off cultures have little or they would seek us out. Surely one imagine the earth covered from no time for the Hollywood alien or or two of them would have horizon to horizon with thick his sinister agenda to be bothered – technologies smarter than ours and woodland and you dropped 300 but this I learned in hindsight. would go exploring and eventually people at random on the Despite the reported sightings there pick up signs of our existence (our surface...what would the chances is zero evidence for alien visitation. radio broadcast for example). Well, be of any two individuals running There are no crashed spacecraft, maybe’s if’s and buts’ and if my into each other within a single life no alien autopsies and no auntie was somewhat differently time. conspiracy. built she would be my uncle. When we think of alien – think alien life or life not native to our earth. You need to widen the definition and be prepared to encounter something a little less complex than Mr Spock from the planet Vulcan… no, Ladies and gentlemen may I introduce to you Slime On Rock (if we are lucky) – more likely simple b a c t e r i a . Remember, for nearly three quarters of the history of life on earth – it was microbial, smaller than the eye can see. And consider this nearly 95% of all life on earth now is Above: Image copyright of http://xkcd.com
smaller than the eye can see. Higher forms of life are possible but probably rare; there is every reason to expect that other planets will have had a roll of the evolutionary dice as well as us, that simple molecules will by chance randomly create a simple cell and by random chemistry a replicator – something that can reproduce. Maybe it happens quite often, more likely it is quite rare – but only needs to happen once! And bingo the clock is ticking – So by all means keep watching the skies but wrap up warm and enjoy the majesty of the heavens, enjoy what is, and dream of what might be.
Declan Molloy is the Ch ai rm an of th e Midlands Astronomy Club (MAC) having been a member for many years. Declan is also enjoys painting and sketching and has painted a number of astronomical objects.
www.midlandsastronomy.com Page - 7
Midlands Astronomy Club Magazine
Midlands Astronomy Club Magazine
Crowdsourcing the hunt for potentially dangerous Asteroids
Four White Dwarfs found eating Earthlike planets It's no fairy tale: Four hungry white dwarfs have been found "snacking" on the shattered remains of Earthlike planets, according to a new study. The findings foreshadow what might happen to our solar system when the sun dies in about five billion years, astronomers say. As stars like our sun run out of nuclear fuel, they swell, becoming red giants. Astronomers think that when this happens to our star, its bulging atmosphere will engulf Mercury, Venus, and maybe even Earth. Eventually, the outer layers of a sunlike star's atmosphere will balloon away to form a nebula, leaving the star's dense core—a white dwarf—shining in the centre. The study authors speculate that any planets not roasted by the star's initial expansion—which takes tens to a few hundred million years— would have their orbits destabilized as the dying star loses mass. The changing orbits would sometimes lead to planets crashing into each other, churning up chunks of rocky debris. Eventually some of these planetary pieces could be nudged so close to the white dwarf that they'd fall into the star and get ripped apart. Evidence for this theory seems to lie in the newly observed white dwarfs' atmospheres, said study leader
Boris Gänsicke, an astrophysicist at the University of Warwick. Normally, a white dwarf' s atmosphere is a mix of only hydrogen and helium, relatively light elements. That's because a white dwarf's intense gravity pulls heavier elements toward the star's core. Any other chemicals in a white dwarf's atmosphere must therefore come from debris falling onto the star's surface. To hunt for signs of planetary consumption, Gänsicke and colleagues looked at 80 white dwarf stars in ultraviolet using the NASA/ESA Hubble Space Telescope. The team found four stars whose atmospheres contain oxygen, magnesium, iron, silicon, and a small bit of carbon—just the elements expected if the stars are absorbing dust from former planets. "The abundances we find are almost exactly the same as those of the entire Earth," Gänsicke said.
Going to the Moon? Don’t touch the historical artefacts Don’t say you haven’t been warned. NASA put out an official document specifying how close any future spacecraft and astronauts visiting the Moon can come to the artefacts left on the lunar surface by all US space missions, including the Apollo landing sites, robotic landing sites and impact sites like LCROSS. While these recommendations are not mandatory (there’s obviously no way to enforce this yet) the document states, “rather, it is offered to inform lunar spacecraft mission planners interested in helping preserve and protect lunar historic artefacts and potential science opportunities for future missions.”
www.midlandsastronomy.com Page - 8
What’s the best way to look for potentially hazardous asteroids? Get as many eyes on the sky as you can. That’s the impetus behind a new partnership between the European Space Agency and the Faulkes Telescope Project, which will encourage amateur astronomers to look for asteroids, as well as providing educational opportunities that will allow students to discover potentially dangerous space rocks, too.
Planets shift their orbits and collid e as they circle a dy ing star in an artist's conceptio n.
"If you could shred the Earth into dust and put it into the white dwarf, it would match the chemical composition." In addition, one star, called PG0843+516, is even more heavily iron-enriched than the other dwarfs and contains high abundances of nickel and sulphur. This makes sense if the star is devouring a chunk of planetary core, the study authors say. "If you think about what the Earth looks like inside, it is almost pure iron and nickel. What we imagine is we see bits of a body that was at some point large enough to have an iron core. The dust seen surrounding the four white dwarfs will be eaten up within "maybe a they want to make sure nothing from previous missions is disturbed. NASA said in an accompanying press release that they recognize the steadily increasing technical c a pa b ilities of s pa ce -far ing commercial entities and nations throughout the world that may be on the verge of landing spacecraft on the surface of the Moon.
For example, NASA recommends an artefact boundary extending 75 m from the Apollo 11 lunar module descent stage.
The document specifies how close another spacecraft can hover, flyover, hop or touchdown near landing sites or spacecraft.
NASA isn’t expecting a rush of astro-looters to descend upon the Moon, but with China discussing a Moon landing, and with several Google Lunar X PRIZE teams hoping to send robotic landers,
And not just hardware is included in the “don’t touch” areas: “U.S. human, human-robotic lunar presence, including footprints, rover tracks, etc., although not all anthropogenic indicators are
few thousand or tens of thousands of years but at some point, another planetary fragment could fall toward the star, creating more of these telltale rocky crumbs," he said. However, the scientists can't tell how many fragments—or even whole planets—might remain around the currently feeding white dwarfs. "We know from studies of other planetary systems that systems come in all kinds of shapes. If there are more lingering worlds orbiting the four white dwarfs, "we don't know [what] the other rocky planets look like and how many there could be, or how stable or unstable their orbits are." www.nationalgeographic.com
protected as identified in the recommendations,” the document says. NASA’s decisions on proximity boundaries were made from recommendations from external experts from the historic, scientific and flight-planning communities and apply to US government artefacts on the lunar surface. NASA says they released this document to open discussions with commercial and international space agencies, and seek any improvements to the recommendations. www.universetoday.com
ESA’s Space Situational Awareness (SSA) program is part of an international effort to be on the lookout for space hazards – not only asteroids but disruptive space weather and space debris objects in Earth orbit.
of Glamorgan in the UK. The project has been active in public education and science outreach, and is a partner of the US-based Las Cumbres Observatory Global Telescope network, which owns and operates two telescopes. Faulkes supports hundreds of But asteroids pose a problem. schools across Europe, offering Often, they are hard to see because free access to their online they can be very dark, they can observing program to schools. approach rather too close before anyone sees them, and they’re The Faulkes project has two often spotted only once and then telescopes where you can sign up disappear before the discovery can for observing online: Haleakala, be confirmed. Hawaii and Siding Spring, Australia. That’s where crowdsourcing comes in, to get more eyes on the skies. “Our new cooperation with ESA is ESA is turning to schools and a great opportunity. Use of the 2 amateur astronomers to help as m-diameter telescopes in Hawaii part of Europe’s contribution to the global asteroid hunt.
and Siding Spring, Australia, will greatly enhance asteroidspotting for the SSA programme, enabling fainter object detection and tracking from a global telescope network,” says Nick Howes, Pro-Am Program Manager at the Faulkes Telescope. “For European students, collaborating on exciting ESA activities and possibly detecting new NEOs is very appealing, as its engagement with one of the world’s great space agencies doing critical scientific work.” While the Faulkes Above: An image of the Faulkes Telescope in project focuses on Hawaii. schools, amateurs will be able to freely access the data archives. ESA’s amateur astronomers have identified archives are also open to all, and hundreds of asteroid candidates, over t h e y w o r k w i t h a m a t e u r 20 of which have been confirmed and astronomers with the Teide named. Find out more about how Observatory Tenerife Asteroid where students in schools across the Survey (TOTAS) team, who use a 1 UK/EIRE and some European -meter telescope at the ESA’s locations can sign up here: Optical Ground Station on Tenerife in the Canary Islands. Since http://www.faulkes-telescope.com/ starting their SSA-sponsored survey www.universetoday.com work in January 2010, the TOTAS
"Stellar Extremophiles" found where star formation isn't supposed to happen
This month, the UK’s Faulkes Telescope Project will become the latest team to formally support the SSA program. Spain’s La Sagra Sky Survey, operated by the Observatorio Astronomico de Mallorca, began helping SSA earlier "We’re finding stars in extreme galactic environments where star this year. formation isn't supposed to “The wider astronomy community happen," explains NASA GALEX offers a wealth of expertise and project scientist Susan Neff. “This enthusiasm, and they have the time is a very surprising development." and patience to verify new sightings; this helps tremendously,” An intriguing double circumnuclear says Detlef Koschny, Head of NEO ring has been discovered at the activity at ESA’s SSA program centre of M83. GALEX, which office. “In return, we share stands for “Galaxy Evolution observing time at ESA’s own Optical Explorer,” is an ultraviolet space Ground Station in Tenerife and telescope with a special ability: It provide advice, support and is super-sensitive to the kind of UV professional validation. We’ll assist rays emitted by the youngest stars. This means the observatory can them in any way we can.” detect stars being born at very The Faulkes Telescope Project runs great distances from Earth, more both educational and research than halfway across the Universe. programs, based at the University The observatory was launched in
2003 on a mission to study how galaxies change and evolve as new stars coalesce inside them. "In some GALEX images, we see stars forming outside of galaxiesin places where we thought the gas density would be too low for star birth to occur," says GALEX team member Don Neil. Stars are born when interstellar clouds of gas collapse and contract under the pull of their own gravity. If a cloud gets dense and hot enough as it collapses, nuclear fusion will kick in and voila! a star is born. The spiral arms of the Milky Way are a "goldilocks zone" for this process. "Here in the Milky Way we have plenty of gas. It’s a cosy
place for stars to form," says Neil. But when GALEX looks at other more distant spiral galaxies, it sees stars forming far outside the gassy spiral disk. The observatory has also found stars being born: in elliptical and irregular galaxies thought to be gaspoor (e.g., 1, 2); in the gaseous debris of colliding galaxies (1, 2); in vast "comet-like" tails that trail behind some fast-moving galaxies (1, 2); in cold primordial gas clouds, which are small and barely massive enough to hang together. According to GALEX, stellar extremophiles populate just about every nook and cranny of the cosmos where a wisp of gas can get together to make a new sun. “This could be telling us something profound about the star-forming process, there could be ways to make stars in extreme environments that we haven’t even thought of yet.” www.dailygalaxy.com
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Midlands Astronomy Club Magazine
Sifting through dust near Orion's Belt Dust is important to astronomers as dense clouds of gas and dust are the birthplaces of new stars. A new image of the region surrounding the reflection nebula Messier 78, just to the north of Orion’s Belt, shows clouds of cosmic dust threaded through the nebula like a string of pearls. The observations, made with the Atacama Pathfinder Experiment (APEX) telescope, use the heat glow of interstellar dust grains to show astronomers where new stars are being formed.
APEX observations are overlaid on the visible-light image in orange. Sensitive to longer wavelengths, they reveal the gentle glow of dense cold clumps of dust, some of which are even colder than – 418 Fahrenheit (–250º Celsius). In visible light, this dust is dark and obscuring, which is why telescopes such as APEX are so important for studying the dusty clouds in which stars are born.
Dust may sound boring and uninteresting, but this new image of Messier 78 and surroundings, which reveals the submillimeterwavelength radiation from dust grains in space, shows that dust can be dazzling. Dust is important to astronomers as dense clouds of gas and dust are the birthplaces of new stars.
One filament seen by APEX appears in visible light as a dark lane of dust cutting across Messier 78. This tells us that the dense dust lies in front of the reflection nebula, blocking its bluish light. Another prominent region of glowing dust seen by APEX overlaps with the visible light from Messier 78 at its lower edge. The lack of a corresponding dark dust lane in the visible light image tells us that this dense region of dust must lie behind the reflection nebula.
In the center of the image is Messier 78 (NGC 2068). When seen in visible light, this region is a reflection nebula, meaning that we see the pale blue glow of starlight reflected from clouds of dust. The
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Midlands Astronomy Club Magazine
clouds reveal gas flowing at a high velocity out of some of the de nse clumps. These outflows are ejected from young stars while the star is still forming from the surrounding cloud. Their presence is therefore evidence that these clumps are actively forming stars. At the top of the image is another reflection nebula, NGC 2071. While the lower regions in this image contain only low-mass young stars, NGC 2071 contains a more massive young star with an estimated mass five times that of the Sun, located in the brightest peak seen in the APEX observations. www.astronomy.com
Saturn’s Moon Titan Even casual observers are gobsmacked by a first glimpse of the rings of Saturn. But keen-eyed beginners will notice a prominent orange “star” near Saturn which follows the planet from night to night. This is no star… it’s Saturn’s largest moon, Titan, one of the largest moons in the solar system and the only moon with a thick atmosphere… By far the largest of Saturn’s moons, Titan makes up nearly 96% of the mass of all bodies orbiting Saturn, including the rings. Titan ranks as the second-largest moon in the solar system after Jupiter’s Ganymede, with twice the mass of Earths’ moon. Titan is larger than the planet Mercury.
Above: This image of the region surrounding the reflection nebula Messier 78, just to the north of Orion’s belt, shows clouds of cosmic dust threaded through the nebula like a string of pearls. The submillimeter-wavelength observations, made with the Atacama Pathfinder Experiment (APEX) telescope and shown here in orange, use the heat glow of interstellar dust grains to show astronomers where new stars are being formed. They are overlaid on a view of the region in visible light. M55 is part of the Messier catalogue; a collection of objects that looked comet-like to the eyes of Charles Messier, a French astronomer working in the 18th century. Messier recorded a list of more than 100 objects which could be confused as comets: galaxies, clusters, and nebulae.
M55 - Or a swarm of angry Bees? Globular clusters are my absolute favourite telescope targets. Okay, Saturn, and then globular clusters. And that’s why I’ve absolutely fallen in love with this amazing picture from the European Southern Observatory of the globular cluster M55, located in the constellation Sagittarius. Globular clusters are my absolute favourite telescope targets. Okay, Saturn, and then globular clusters. And that’s why I’ve absolutely fallen in love with this amazing picture of the globular cluster M55, located in the constellation Sagittarius. Globular clusters contain vast numbers of stars clumped together in a tight area. In the case of M55, there are about 100,000 stars grouped up within a sphere only 100 light-years across. Astronomers know that globular clusters are old, almost as old as the Universe itself.
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M55 is thought to have formed 12.3 billion years ago. The most ancient stars in the cluster burned out a long time ago, detonating as supernovae. We’re now left with the cooler, lower mass stars, which slowly wink out one-by-one becoming white dwarfs. Our own Sun is only halfway through its own lifespan, before it runs out of hydrogen fuel and becomes a white dwarf. There are at least 160 globular clusters scattered across the Milky Way, grouped up more towards
our galaxy’s core. We can only see some of the clusters because the bright core of the Milky Way obscures our view to objects on the other side. But other galaxies, with their own globular clusters show us what our own galaxy probably looks like from afar.
To see M55 on your own you’ll need at least a pair of 50 mm binoculars or a small telescope, some nice dark skies, and a clear view to the constellation Sagittarius. Sagittarius looks exactly like a teapot in the sky, hovering above the southern horizon in summer. www.universetoday.com
Saturn’s rings. You can see this big moon with binoculars, while the rings are visible only in telescopes. In a larger scope, some observers can even resolve Titan into a tiny orange disk… a tantalizing glimpse of this distant, icy world. While Titan is the biggest of Saturn’s satellites, the planet has some 62 moons with confirmed orbits. Of this large collection, nine were discovered with telescopes before the age of spaceflight. They are, in increasing distance from Saturn: Mimas, Enceladus, Tethys, Dione, Rhea, Titan, Hyperion, Iapetus, and Phoebe. The moons were named after the Titans of ancient Greek legend.
Titan is also the only Moon with a substantial atmosphere, which is made mostly of nitrogen along with traces of methane and other organic molecules. Titan has lakes of liquid hydrocarbons and hills and dunes and boulders of frozen water (see image above). The presence of organic molecules suggests Titan may have the right chemistry for simple forms of life to develop, so planetary scientists intensely study With a 6″ or 8″ telescope, you can this massive moon. see as many as five of Saturn’s moons– Titan, Enceladus, Dione, For us backyard observers, Titan Tethys, and Rhea. The moons presents an easier target than move from night to night, much
tan as largest moon Ti Saturn and its all telescope. sm a in ar pe it might ap
like Jupiter’s moons, so they are tricky to track. Sky & Telescope publishes a free Javascript utility to help you sort out which moon is which. You can find it here: http://www.skyandtelescope.com/ o b s e r v i ng / o b j e c ts / j a va s c r i p t / saturn_moons# www.oneminuteastronomer.com
A Universe with billions of Binary Planets? The discovery that there are perhaps billions of solo rogue planets and binary planet systems in the Milky Way alone has led to a new theoretical study by astronomer Hagai Perets and his colleague at the Harvard-Smithsonian Centre for Astrophysics that proposes a possible answer: the distant planets are not part of the original stellar system - they were captured by the star. Astronomers know that there are many so-called "free floating planets" in space - planets that have been tossed out of their original solar system by a random gravitational encounter with another planet. Some of these orphan planets have recently been detected.
nearby to interfere with the "adoption." They ran a series of computer simulations to test all these and other possibilities, and they found not only that such a capture was possible, but that a star could even capture several orphan planets.
The CfA team calculated that it would be possible for a star to capture one of these orphans if the conditions were right; namely, if the star and planet happen to pass close to each other with only a small velocity difference, and if there are no other massive bodies
In fact, they found that sometimes two free floating planets could capture one another and form a binary planet. None of these binaries has yet been seen, although some
astronomers think that since Pluto and its moon Charon have such similar masses they are a binary system, although not necessarily one that was captured. The new results seem to offer a reasonable, if exotic, explanation for some of the complex planetary configurations that have been discovered, and they remind us that nature is full of surprises. www.dailygalaxy.com
To help find your way around the night sky, Skymaps.com makes available for free each month a map of the night sky. The Evening Sky Map is suitable for all stargazers including newcomers to astronomy and will help you to:
• Identify planets, stars and major constellations.
• Find sparkling star clusters, wispy nebulae & distant galaxies.
• Locate and follow bright comets across the sky.
• Learn about the night sky and astronomy.
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Midlands Astronomy Club Magazine
Midlands Astronomy Club Magazine
Kid’s Korner How long does each phase of the moon last? What people sometimes call "moonlight" is really sunlight reflecting off the Moon's surface. The Moon itself puts out no light at all. It takes about four weeks for the Moon to orbit once around Earth. During this time, the Moon's position relative to Earth and the Sun is turn just a little tiny bit to your left, constantly changing. still holding the ball straight out. You will see only a thin lighted During part of its journey, the Moon crescent on the right side of the is between Earth and the Sun. Then, ball. Now turn to the left a little a few days later, it is off to one side. more until the light is on your right. Still later, the Moon moves around You will see half the lighted side of so that Earth is between it and the the ball. This position represents the First Quarter phase of the Sun. And so on. Moon. Now turn to the left again, Try this little demonstration. You will so the lamp is behind you. (If the need a lamp and a small ball (like a ball is directly in the shadow of tennis ball or a softball). If the lamp your head, raise the ball up a little has a shade, take it off. Pretend the higher.) You will see the entire lamp is the Sun, the ball is the lighted side of the ball. Now you Moon, and your head is Earth. Dark- are looking at the Full Moon. Now turn again so the lamp is on your en the room except for the lamp. left. Now you are looking at the Now, hold the ball straight out in Last Quarter phase. front of you. Stand facing the lamp. The ball will appear dark because The Moon's orbit actually dips a the lighted side of the ball is facing little bit above and below an away from you. T h i s imaginary line drawn between position represents the New Moon, Earth and the Sun. That is why dark and about to be born. Now, Earth seldom blocks the Sunlight
A diagram showing the phases of the moon. The inner circle shows the moon being highlighted by the sun and the outer circle shows how this reflection appears to us here on Earth.
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from reflecting off the full Moon. Once in a while, though, Earth does get directly in the way, and we have the exciting event called a lunar eclipse. This month, go outside each day or evening and observe the Moon moving through its phases. At night, look carefully, especially when the Moon is just a crescent, and find the dark part of the Moon. We can see the dark part because it reflects Earth light-that is, Sunlight reflected from Earth. So, how long does each phase of the Moon last? Well, the phases are just names we give to certain points along the Moon's smooth path around Earth. Technically, each phase, just like the one called a New Moon, when the Moon is exactly between Earth and the Sun, lasts only a brief instant. But to our eyes, a New Moon can last for a few days, representing the time that the Moon appears in the sky too near the Sun's position for us to see it at all. The time it takes the Moon to go through all its phases is about a month, and that was so important to our ancestors that they created the period of time we
Planets orbiting the Sun inside Earth's orbit show phases as in this drawing. When the other planet is nearest Earth (called inferior conjunction) it appears in its "new" phase. When farthest from Earth on the other side of the Sun (called super- ior conjunction), it is in its "full" phase and visible only around sunset or sunrise.
Your guide to the Transit of Venus
Venus in its gibbous phase, photographed by the Galileo spacecraft. call a month. Maybe you've even noticed that the word month is like the word moon. It isn't just the Moon that appears to have phases. The planets also have phases. For example, the orbit of Venus is inside the orbit of Earth. When Venus is in the part of its orbit between Earth and the Sun, we can't even see it, because its sunlit side will be away from us. This position is similar to the New Moon phase. As Venus progresses around the Sun, more and more of its illuminated side is visible to us on Earth. When Venus is on the far side of the Sun, we will see its Full Phase. At this time, we will see Venus only around sunset or sunrise, when the sky is just dark enough to see it even though Venus appears in the sky near the Sun.
On June 5-6 you get your last chance to see one of the rarest of astronomical events, the Transit of Venus, during which the black disk of Venus passes across the glowing disk of the Sun. This transit has happened just seven times since the invention of the telescope more than 400 years ago. The last transit was in 2004. There won’t be another until December 2117. Here’s how and where to see next month’s transit for yourself… Where To See The Transit The maps below shows where the 2012 transit of Venus is visible…
Even Earth has phases, as viewed from the Moon. Photos taken of Earth by Apollo astronauts show part of Earth in darkness and part lit by the Sun.
The western and central Pacific, including most of Australia, New Zealand, Fiji, and Hawaii can see the entire transit. Western and southern Africa, Spain and Portugal, and eastern South America will not see the transit at all because it occurs when the sun has set. And the rest of the world can see some of the transit after the Sun rises or before it sets. Here in Ireland we will only get to see the last 47 minutes of the transit.
Planets orbiting the Sun outside Earth's orbit show phases as in this drawing. When Earth is positioned on a line between the Sun and the other planet called opposition), the planet is in its full phase and shines brightly in Earth's night sky. When farthest from Earth on the other side of the Sun called conjunction), the other planet also appears full, but is visible only around sunset or sunrise.
Why It Happens Like a solar eclipse, a transit occurs when Venus, rather than the Moon, passes between Earth and the Sun. And like a solar eclipse, the transit requires careful alignment of the Sun, Earth, and Venus. As seen from Earth, Venus usually passes over or under the Sun every 584 days, on average. But the geometry and periods of the orbits of two planets cause Venus to pass in front of the Sun at well-defined intervals of 121.5 and 101.5 years in either June or December. And the transits occur in pairs separated by eight years. The last transit occurred on June 8, 2004. The last pair of transits were on December 1874 and December 1882.
The Transit of Venus once held the key to understanding the size of the solar system. In the early 18th century, Edmund Halley determined a way to measure the distance from the Earth to the Sun by precisely timing the transit of Venus from widely separated parts of the Earth. Once this distance was known, the distances to other planets could be determined through Kepler’s Laws. These transits were so important that most advanced nations sent astronomers around to world to measure the events of 1761 and 1769. The transit of Venus in 1761 yielded few conclusive results despite hundreds of attempted measurements. But the transit of 1769 was measured precisely by, among others, the team led by Lieutenant James Cook, RN, who witnessed the event from Tahiti before sailing on to claim Australia for England. Astronomers used Cook’s measurements to calculate a distance to the Earth of 150 million kilometres, close to the nowaccepted value of 149,597,870.7 kilometres. How To See The Transit For this June 5-6 transit, Venus will traverse the northern half of the Sun’s disk. You’ll get the best view of the transit with a telescope, but a telescope is not required. Telescope or not, you’ll need a safe solar filter. Here’s some advice on finding a solar filter suitable for observing this event. If you don’t have your own filter, check if your local astronomy club is holding a public event during the transit.
Above: On June 8, 2004, a rare celestial event the Venus transit, the apparent crossing of our planetary neighbour in front of the sun was captured from the unique perspective of NASA's sun-observing TRACE spacecraft. The top image shows Venus on the eastern limb of the sun. The bottom left image is in the ultraviolet, and the bottom right image is in the extreme ultraviolet. The last V " enus transit"occurred more than a century ago, in 1882, and was used to compute the distance between Earth and the sun. Scientists with NASA's Kepler mission hope to discover Earth-like planets orbiting other stars by searching for transits similar to this one. If people miss this months transit there will not be another one until Dec. 11, 2117. They’ll have properly equipped scopes and other hardware to help you enjoy this rare event. The transit of Venus unfolds in four stages. First, the leading edge of the planet contacts the Sun. Then the trailing edge makes contact, which is hard to time exactly because of the “black drop effect” that bleeds darkness from the limb of the planet as it moves onto the solar disk. The same two stages reverse themselves as the planet leaves the solar disk. The June 5-6, 2012 transit takes about 6 hours, which is a long time compared to the scant few minutes of a solar eclipse.
fact, uses this same idea… a transiting planet blocking light from its home star… to look for Earth-like planets around nearby stars. Astronomers will use the 2012 transit of Venus to test new measurement techniques to find extra-solar planets using spacebased telescopes. The history and the rarity and the beauty of this event make it a compelling and memorable sight. Please… observe it for yourself if you can. www.oneminuteastronomer.com
During the transit, the black disk of Venus, just 33x smaller than the solar disk, blocks enough light to measurably decrease t he Sun’s brightness. NASA’s Kepler observatory, in
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Midlands Astronomy Club Magazine
Four White Dwarfs found eating Earthlike planets ................. 8 Going to the Moon? Don’t touch the historical artefacts ......... 8 Saturn’s Moon Titan ............................................................ 9 A Universe with billions of Binary Planets? ............................ 9
Kids Section Front cover image: This Star formation in the Tarantula Nebula is the largest, most violent region known in the whole Local Group of galaxies land lies in our neighbouring galaxy the Large Magellanic Cloud (LMC). Were the Tarantula Nebula at the distance of the Orion Nebula, a local star forming region, it would take up fully half the sky. The above image is one of the largest mosaics ever created by observations of the Hubble Space Telescope and has revealed unprecedented details of this enigmatic star forming region. The image was released to celebrate the 22nd anniversary of Hubble's launch.
Credit & Copyright: NASA, ESA, ESO, D. Lennon (ESA/STScI) et al., and the Hubble Heritage Team (STScI/AURA)
Kids Korner ....................................................................... 10
Quizzes and Games Exercise your brain ............................................................ 11
Monthly Sky Guide Beginners sky guide for this month .................................... 12
Internet Highlights Special content only available with the online version of the magazine ................................................................ 13
Hoy and Ho Tsung and Chang Hsi and Ho Chin and Hsi
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3. In what year did Galileo Galilei begin using the recently invented optical 9. In the year 14,000 telescope to observe the which star will be the heavens? pole star? 1604 Thuban 1608 Vega 1610 Polaris 1609 Sirius 4. What is the magnitude 10.In which vast area of the Sun from Earth? (50,000-100,000 A.U. in -25 extent) are most long-26.36 period comets believed -27.4 to originate? -26.72 Kuiper Belt 5. Which planet in our solar system is less dense than water which means that if all the planets were put into a huge ocean this planet would float? Uranus Jupiter Saturn Pluto
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Check your answers on this page. Answer 5: The correct answer was Saturn.
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Answer 1: The correct answer was Mimas. Mimas is the smallest of Saturn's moons and is heavily cratered due to frequent impacts throughout history. The Herschel Crater, which is named after the astronomer William Herschel, is all that remains of the object that almost shattered the small moon and makes it look like the Death Star from Star Wars.
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Answer 7: The correct answer was 365.256 days. A sidereal year is the time it takes the earth to complete one circuit around the sun. It is 20 minutes longer than a tropical year.
"Stellar Extremophiles" found where star formation isn't supposed to happen ..................................................... 5
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Answer 8: The correct answer was 365.242 days. A tropical year is the time measured from equinox to equinox. It is 20 minutes shorter than a sidereal year.
You can see more about the club and its events on www.midlandsastronomy.com or contact the club via e-mail at midlandsastronomy@gmail.com Meetings are informal and are aimed at a level to suit all ages.
Crowdsourcing the hunt for potentially dangerous Asteroids ............................................................................ 5
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Answer 2: The correct answer was Hsi and Ho. Back in the time of Hsi and Ho the Chinese believed that a solar eclipse was caused by a great dragon trying to eat the sun. They believed that creating a lot of noise would scare it away and when the eclipse of 2136 B.C. caught them off guard they thought it was just good fortune that the sun was not consumed by the monster.
M55 - Or a swarm of angry Bees? ........................................ 4
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Answer 9: The correct answer was Vega. This is due to precession and although it might look as if the stars in the night sky are fixed in space they are actually rotating around the galaxy as is our own sun.
Sifting through dust near Orion's Belt ................................... 4
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Answer 3: The correct answer was 1609. The first telescopes were invented by lens makers in the Netherlands in 1608 and within a year Galileo Galilei had turned them on the sky.
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1. Which moon of Saturn 6. Which of the four great Galilean moons around was almost shattered by Jupiter is the closest to the object that produced the planet? the Herschel Crater on its surface? Ganymede Iapetus Europa Mimas Callisto Titan Io Rhea 7. How long is Earth's sidereal year? 2. In 2136 B.C. the two Imperial Court 365.87 days astronomers in China 365.256 days were executed for not 365.242 days predicting a solar 364.987 days eclipse. Name them?
Answer 10: The correct answer was the Oort Cloud.
Latest Astronomy and Space News
All are welcome to attend. It also holds infrequent Observing Nights at its Observing Site in Clonminch, or at a member’s house (weather permitting) on the first Friday of every month..
Exercise your brain
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Answer 4: The correct answer was -26.72. The Sun is the brightest thing we see from Earth. In comparison the full moon is -13 and at it's brightest Venus is -4.4.
MAC meets on the first Tuesday of the month in the Presbyterian Hall, High Street, Tullamore from 8pm.
Midlands Astronomy Club Magazine
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Midlands Astronomy Club Magazine
Sky Guide - Beginner’s targets for June
Issue 34- June, 2012
General notes Ahh, the summertime offers wonderful observing weather (and with it mosquitoes and every other kind of annoying insect so don't forget your bug-spray). While we don't get to observe until later in the evening, it sure is nice to be able to shed all those layers of clothing for some comfortable shorts and t-shirts‌ well OK then wet gear and wellies. There is a weak meteor shower this month, the June Lyrids, which peaks on the 15/16th of the month. Unfortunately the maximum rate observed is only about 8 per hour which is around the same intensity as the sporadic rate visible on any given night. Telescope Targets Many of the targets from April and May are still available for viewing in June. See the previous editions for their descriptions. T he N orther n H em is pher e 's premier globular cluster comes into good position this month. The Great Hercules Cluster (M13) is easily located by using 2 of the stars in the "keystone" of the constellation Hercules, namely Eta and Zeta Herculi. These are the 2 stars that form the top of the Keystone (the Western side). On line directly between these 2 and approximately a third of the way from Eta to Zeta is the cluster.
Above: A sky chart showing the centre of the Lyrid meteor shower. Look for the star Vega as a guide. Don't be afraid to try and use higher powers on this one. This cluster contains approximately a million stars and is over 100 light-years in diameter. It's located approximately 25,000 light-years from us and age estimates indicate that it is nearly 10 billion years old. Another globular cluster within the Hercules cluster is M92, while not as bright as it's more famous neighbour it's still a wonderful sight through any telescope. M92 forms an equilateral triangle with the top 2 stars in the Keystone (Zeta and Pi). M92 contains several hundred thousand stars approximately 100 light-years in diameter. It's located approximately 35,000 light-years away.
Club Notes Club Observing: The next club meets every 1st and 3rd Saturday of the month for our observing sessions held in the MAC grounds. If you wish to be informed of these sessions please email your name and mobile number to midlandsastronomy@gmail.com who will confirm if the session is going ahead (depending on weather).
MAC is a proud member of
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M13 was discovered by Edmond Halley in 1714, and catalogued by Charles Messier on June 1, 1764. It is estimated that M13 is about 145 light-years in diameter, and that it is composed of several hundred thousand stars. M13 was also aiming point of the first interstellar message known as the Arecibo message in 1974. This message was designed to communicate the existence of human life to hypothetical extra-terrestrials. The reason M13 was chosen was that with a higher star density, the chances of a life harbouring planet with intelligent life forms, were higher. That and the fact that is was well placed in the sky on the night in question.
Planets This month Mercury is visible as an evening object in the second half of the month and sets by around 23:15 in the evening.
The red planet (Mars) is visible as soon as darkness falls as is Saturn also. While Jupiter, Uranus and Neptune are all morning objects this month.
This month the big highlight is Venus which will transit the Sun on the morning of the 6th. On that morning sunrise is at around 04:50 and fourth contact when the planet slips off the sun’s disk occurs at 05:53. This gives a window of around 1 hour to see this event. This would be well worth observing as it is another 105 years to the next one! Never view the Sun directly with the naked eye or with any unfiltered optical device, such as binoculars or a telescope! Make sure you use proper solar filters to observe this safely.
General notes Check out www.heavensabove.com for the latest passes of the International Space Station and satellites, details of Space Shuttle launches and passes and for details of Iridium Flare activity. Clear skies and good hunting!
Latest Astronomy and Space News Kids Astronomy Quizzes and Games
By Kevin Daly http://members.aol.com/kdaly10475/index.html
Monthly Sky Guide Internet Highlights
Midlands Astronomy Club Magazine
Midlands Astronomy Club Magazine
Internet Highlights Each month we will try and bring you the best of the web for astronomy online resources such as movies, podcasts and free software. If you have any suggestions for content in these pages please contact us at midlandsastronomy@gmail.com
ESA Euronews: Unveiling Venus It can be called the morning or evening star, depending on where you are or what time it is, but it is anything but a star. In fact, it is one of our nearest planetary neighbours. Venus and Mars may be Earth's close cousins, but they are oh-so different. Only now are we starting to peer through Venus' clouds to reveal the burning planet's secrets.
http://youtu.be/ZIp94ZM_VDs
Transit of Venus Part One
Transit of Venus Part Two
Please click on the links provided to view the material and not the images.
How To Measure the Universe
Asteroid Discovery from 1980 - 2011
This year will be the last Transit of Venus to be seen in our lifetime. The next will not occur until 2117. To mark the occasion, NASA will set up a live telecast of the event from Hawaii which is the best place to view it.
http://youtu.be/I1qi4tPDW_k
http://youtu.be/OAx-_iuCq14 http://vimeo.com/41434123
http://youtu.be/ONUSP23cmAE
Is Pluto a planet?
Podcast: Exploration of Venus Mars gets all the attention, but you might be surprised to know how much Venus has been explored. From initial telescope observations and the early flyby missions, to the landers… yes landers and orbiters. We know quite a lot about Venus, but the planet sure didn’t give up its secrets easily. http://www.astronomycast.com/
Podcast: The Jodcast
No matter how much evidence is put before them, some people just won’t let this issue end. http://youtu.be/Z_2gbGXzFbs
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A podcast about astronomy including the latest news, what you can see in the night sky, interviews with astronomers and more. It is created by astronomers from The University of Manchester's Jodrell Bank for anyone interested in things out of this world.
Useful free astronomy resources Midlands Astronomy Club have created a Facebook page so that our members and non-members alike can: • Keep up-to-date on future outreach events. • Be informed of upcoming lectures. • Have online access to the latest astronomy news as it happens. • See photos of all club events and activities. Find us on www.facebook.com
IFAS Website
http://www.irishastronomy.org
Stellarium
http://www.stellarium.org
Virtual Moon Atlas
http://www.astrosurf.com/avl/UK_index.html
Celestia
http://www.shatters.net/celestia/index.html
Sky Maps
http://skymaps.com/index.html
Heavens-Above
http://www.heavens-above.com/
http://www.jodcast.net/archive/
www.midlandsastronomy.com Page - 14
Midlands Astronomy Club Magazine
Midlands Astronomy Club Magazine
Internet Highlights Each month we will try and bring you the best of the web for astronomy online resources such as movies, podcasts and free software. If you have any suggestions for content in these pages please contact us at midlandsastronomy@gmail.com
ESA Euronews: Unveiling Venus It can be called the morning or evening star, depending on where you are or what time it is, but it is anything but a star. In fact, it is one of our nearest planetary neighbours. Venus and Mars may be Earth's close cousins, but they are oh-so different. Only now are we starting to peer through Venus' clouds to reveal the burning planet's secrets.
http://youtu.be/ZIp94ZM_VDs
Transit of Venus Part One
Transit of Venus Part Two
Please click on the links provided to view the material and not the images.
How To Measure the Universe
Asteroid Discovery from 1980 - 2011
This year will be the last Transit of Venus to be seen in our lifetime. The next will not occur until 2117. To mark the occasion, NASA will set up a live telecast of the event from Hawaii which is the best place to view it.
http://youtu.be/I1qi4tPDW_k
http://youtu.be/OAx-_iuCq14 http://vimeo.com/41434123
http://youtu.be/ONUSP23cmAE
Is Pluto a planet?
Podcast: Exploration of Venus Mars gets all the attention, but you might be surprised to know how much Venus has been explored. From initial telescope observations and the early flyby missions, to the landers… yes landers and orbiters. We know quite a lot about Venus, but the planet sure didn’t give up its secrets easily. http://www.astronomycast.com/
Podcast: The Jodcast
No matter how much evidence is put before them, some people just won’t let this issue end. http://youtu.be/Z_2gbGXzFbs
www.midlandsastronomy.com Page - 13
A podcast about astronomy including the latest news, what you can see in the night sky, interviews with astronomers and more. It is created by astronomers from The University of Manchester's Jodrell Bank for anyone interested in things out of this world.
Useful free astronomy resources Midlands Astronomy Club have created a Facebook page so that our members and non-members alike can: • Keep up-to-date on future outreach events. • Be informed of upcoming lectures. • Have online access to the latest astronomy news as it happens. • See photos of all club events and activities. Find us on www.facebook.com
IFAS Website
http://www.irishastronomy.org
Stellarium
http://www.stellarium.org
Virtual Moon Atlas
http://www.astrosurf.com/avl/UK_index.html
Celestia
http://www.shatters.net/celestia/index.html
Sky Maps
http://skymaps.com/index.html
Heavens-Above
http://www.heavens-above.com/
http://www.jodcast.net/archive/
www.midlandsastronomy.com Page - 14