Astronomy Wise May 2013 Astronomy Magazine by David Bood

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CONTENTS 6 ROGUES

GALLERY

8 A BRIEF HISTORY OF SOLAR ASTRONOMY PT 2 18 DEEP SKY IMAGING PT 4 PHOTOSHOP 22 NEWS IN BRIEF 26 NORTHERN LIGHTS 32 TYCHO’S SUPERNOVA 34 THE NIGHT SKY– SEE WHAT TO VIEW THIS MONTH 42 LETS TALK INTERVIEW—DR CLAUDIA ALEXANDER 48 When Stars Die 52 A SOUTH AFRICA IMAPCT CRATER 54 DAYSTAR SOLAR SCOPE 56 ASTRONOMY ART 58 SATURN 64 Star Clusters 66 Astronomy Wise

Background Image: Henna Khan Partial Lunar Eclipse

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Editors Note…… Welcome to another edition of the Astronomy Wise digital magazine. This month sees my last edition for a while, Edward Dutton will be taking over the editor role. We have another packed issue for you full of article, news and our interview with NASA’s JPL Rosetta project Manager Dr Claudia Alexander. Mike Greenham continues his imaging workshop with part 4, looking how to edit your photographs. Julian Onion looks at what happens when a star dies and Pepe continues with the X-Ray sky. We have some amazing photographs of the Northern Lights taken from Norway see page 26 for more details. So please enjoy our latest offering from our corner of the universe. Ed: Dave Bood

CONTACTS David Bood—dbood@astronomy-wise.com Edard Dutton— astronomywisedesignteam@gmail.com Jason Ives— astronomywiseimages@gmail.com Mike Greenham @AstroMike247 Pepe Gallardo @aechmu Julian Onions @julianonions

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Whoâ&#x20AC;&#x2122;s Who?

Jason Ives

David Bood

Design

Co founder

Co Founder

Logo Design

Rogues Gallery

Editor @AstronomyWise

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From Left to Right Top: Andrew Devey, Mike Greenham, Pepe Gallardo, Julian Onions

Sky notes John Harper FRAS www.astronomy-wise.com

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A brief history of solar astronomy – Part 2

In the late 1850s Robert W Bunsen and Gustav Kirchoff expanded on Fraunhofers spectral lines and compared them to laboratory observations of the spectrums in heated pure gases. They were able to demonstrate in 1859 that the Sun contained a large number of chemical elements that were mostly metals. The total solar eclipse of 18 July 1860 was the most thoroughly observed up to that time was mainly recorded by drawings later evaluation of a peculiar feature on the SW limb when compared to modern coronographs reveal what is likely the first record of a coronal mass ejection in progress!

Jules Janssen

Hydrogen was recognised spectroscopically by A Ångstrӧm in 1862. In 1868 J. Norman Lockyer and Jules Janssen had the same idea to use a spectroscope to observe the Sun through a very restricted wavelength centred on the red part of the visible spectrum. They were able to observe prominences for the first time in broad daylight and dispel the idea that these features were part of the Moon’s atmosphere. Lockyer had seven prisms mounted on a wheel behind his eyepiece to achieve the required band width for these observations. This was equivalent to modern hydrogen alpha solar telescopes.

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During one solar eclipse they investigated a prominence spectrum and noted an emission line in the yellow part of the spectrum that did not correspond to any known chemical element, they continued investigations with the new observing method and Lockyer suggested that this line was due to an element thus far unknown on Earth that he subsequently named Helium [from the sun god Helios in ancient Greek mythology]. Later in 1895 William Ramsey was able to isolate Helium in a laboratory. The new method of observing the Sun’s outer atmosphere led to rapid advances in solar physics and Lockyer and Janssen received a commemorative medal bearing their images from the Academie des Sciences de Paris.

In 1869 Charles A. Young and William Harkness independently noticed a feint emission line in the green part of an otherwise featureless coronal spectrum. They ascribed it in 1876 to a mysterious chemical element “Coronium”.

Chemist William Ramsey

He also assumed thermal equilibrium enforced by convection motions leading to stratification and described a rise in density and temperature when moving from the surface toward the sun’s centre. He used the Sun’s mass and radius to get the density profile of the surface and the perfect gas law to estiBy the 1860’s through the spectroscopic mate the sun’s outer temperature but work of Kirchoff and others they had his results were five times too high by offered strong evidence that the solar modern standards inferred through atmosphere was in a gaseous form and spectroscopic means. hot. By 1881 it had become increasingly Jonathan H. Lane published a paper in clear that the earth’s atmosphere was the American Journal of Science and absorbing a significant proportion of the Arts in 1870 that presented the first sun’s luminosity. Later attempts to mathematical model of the solar determine the sun’s luminosity were interior. He assumed that the Sun’s mover to the highest practical altitudes. interior was gaseous and chemically Samuel Langley led an expedition to homogeneous throughout, that is was in Mount Whitney California and calculated a state of hydrostatic equilibrium with a value for the solar constant of 2903 inward gravitational pull being balanced Watt per square metre and twice that of by an outward gradient of gas pressure. modern calculated values. Later his

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assistant Charles Abbot obtained 1465 W/m² using the same original data. In 1899 the Kirstian Birkland set out to study the Aurorae Borealis and concluded that they are caused by the episodic arrival of beams of charged particles from the Sun that were deflected and guided to high geographic latitudes by the Earth’s magnetic field. He later went on to produce artificial Aurorae in his laboratory. Walter and Annie Maunder were plotting the latitudes of sunspots and in 1904 they produced the first butterfly diagram. Over each successive solar rotation they used a vertical line segment spanning the range where sunspots were observed and these were drawn on a time-latitude diagram. This diagram clearly shows that the sunspots for a new cycle start at higher latitudes and that they drift toward the sun’s equator as the cycle proceeds. These butterfly diagrams are still used today to compare the different solar cycles.

Walter and Annie Maunder were plotting the latitudes of sunspots and in 1904 they produced the first butterfly diagram. Over each successive solar rotation they used a vertical line segment spanning the range where sunspots were observed and these were drawn on a time-latitude diagram. This diagram clearly shows that the sunspots for a new cycle start at higher latitudes and that they drift toward the sun’s equator as the cycle proceeds. These butterfly diagrams are still used today to compare the different solar cycles. Below: Photograph of the first sunspot butterfly diagram, drawn in 1904 by Walter and Annie Maunder. Edward Walter Maunder

Source: http://www.astro.umontreal.ca

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It was believed since Kirchoff that the solar atmosphere was made of a layer of cool gas, illuminated from below by the hotter solar interior. In the second part to the nineteenth century yielded results incompatible with a simple inert and absorbing atmosphere. Progress by Arthur Schuster who in a series of papers written between 1903 and 1905 investigated the passage of radiation through an atmosphere that can not only absorb, but also emit and scatter and re-emit the light traversing it. A full model of the solar atmosphere based on radiative equilibrium was developed by Karl Schwarzchild in his 1906 paper showed

that the observed limb solar darkening profile pointed to a state of radiative equilibrium, rather than the adiabatic stratification expected to result from convective equilibrium. Schwarzschild's paper opened the door to the physical interpretation of stellar spectra, and more generally to the construction of realistic structural and evolutionary models of the sun and stars. By 1908 the magnetic nature of sunspots was confirmed by George Ellery Hale and collaborators by measuring Zeeman splitting in magnetically sensitive lines in the spectra of sunspots and the detection of

polarization of the split spectral components. He had proved that sunspots are the seats of strong magnetic fields. This was not only the first detection of a magnetic field outside the Earth but the sunspots had magnetic strengths over a thousand times greater than that of the Earthâ&#x20AC;&#x2122;s own magnetic field. These discoveries lead to the discovery of lower temperatures within the sunspots when compared to the temperature of the photosphere. By 1910 Enjar Herzsprung and Henry Norris Russell had produced a scatter graph of the stars showing the relationship between the starsâ&#x20AC;&#x2122; absolute magnitudes or luminosities verses their spectral type or classification and effective temperatures. They plotted each star on a graph and this represents a major step towards the understanding of stellar evolution or the lives of stars.

Above: Henry Norris Russell Below: Enjar Herzsprung

Hale in 1919 went on to show that large sunspots pairs almost always show the same magnetic polarity pattern in each solar hemisphere, show opposite polarity patterns between the North and South solar hemispheres, and these polarity patterns are reversed from one sunspot cycle to the next, indicating that the physical magnetic cycle has a period of twice the sunspot cycle period. The theory of the solar internal structure was www.astronomy-wise.com

further developed by Arthur Stanley Eddington between 1916 and the publication of his book “The Internal Constitution of the Stars” in 1926. The mass-luminosity relation predicted by Eddington’s stellar structure was compared to the then available data for various types of stars and showed good agreement and provided strong empirical evidence to support his theory. One vital piece was still missing the internal source for the Sun’s energy.

Albrecht Unsöld (1905 - 1995) Image Source: http://www.uni-kiel.de

Albercht Unsöld established in 1928 the preponderance of Hydrogen in the Sun on the basis of a few spectral lines. Henry Norris Russell concluded in 1929 that Hydrogen was the dominant constituent in the solar atmosphere followed by Helium with metals present in very small quantities. Much of the progress made in understanding the Sun’s outer atmosphere had been made diring the brief times of total solar eclipses. In 1931 Bernard Lyot designed and used an instrument that is now known as a

coronagraph. This was a telescope equipped with an occulting disk designed to block out the solar disk. Lyot managed to take the first full daylight photographs of the solar corona. In the mid 1930’s spectroscopic coronal observations by Lyot revealed feint coronal emission lines with much broader wavelengths than expected. He assumed this broadening was the result of a thermal nature and inferred coronal temperatures of around 600,000 K. This was met with due caution at the time. By 1941 acceptance of the very high coronal temperatures was confirmed by the spectroscopic work of Walter Grotrian and Bengt Edlén. The coronal green lines tentatively named by Young in 1869 as “coronium” were associated with high ionization stages of Iron (Fe) and Nickle (Ni). This required coronal temperatures initially estimated at over 250,000 K that soon rapidly rose to 1-2 million K. To be continued. Have fun with our Sun Andy Devey

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Part 4 Basic Processing of your Images in Photoshop In this part I will attempt to show you how after capturing your image you can process it in Photoshop to bring out the all the detail. While I show it in Photoshop the same procedure can’t be carried out in GIMP (a free photo editing suite available online). I’m going to use an image of M51 I recently captured to demonstrate the procedure’s. Here we will look at levels, curves, vibrance, saturation, noise and sharpness. Processing contains a lot of artistic licence. There is no right or wrong way to do it. It’s a matter of making little adjustments to enhance your image. I’ll show you the basics here but the best way to learn is to play with you images and see how adjustments affect them. Firstly lets open the image and see what we have. As you can see the background appears grey so let’s address that first. Go into levels and you will see the histrogram of the image. The histogram shows us a graph of the data we collected and how it is distributed. The higher the peak the more data at that level. The black, grey and white arrows under the histogram show us the set point of the black, greys and whites which we can slide to modify these levels. You can see that at the beginning of the histogram there is a blank. No data is contained here so we can slide the black arrow along to the start of the histogram. This we have the effect of darkening the sky by moving the black set point. The Grey arrow can now be slid either way to bring out more faint detail. Its best to just play and see what affect the movement has. I wouldn’t move the white arrow as you can see there is data above it so if we did move the arrow it will clip this data. You can repeat this step several times until you think it’s right but be careful you don’t introduce too much noise. Next we want to look at the Curves. Here we can stretch the curve bringing out that faint data. You can see the bottom arrow shows the three points I have put in and www.astronomy-wise.com

stretched the curve so that that data is intensified in that part of the graph. Keep playing with these points dragging them up/down/left and right and see how the Image changes. You can determine which part of the histogram relates to a certain area of the image by selecting the pointer shown by the red arrow on in the picture on the left. Once selected move your cursor across the image and youâ&#x20AC;&#x2122;ll see a small circle moving around in the histogram. Click your mouse on the area of the image you wish to stretch and it will put a corresponding point in the histogram. Then click that point and you can drag the curve about to stretch the image.

The image above shows what we have now after our levels and curves adjustments and you can see its starting to look much better. It still looks a little washed out so now we can adjust the Vibrancy and Saturation to intensify the colours. Another method to adjust the colour would be to use colour match. This can be found as seen in the picture on the left. Here you can also adjust the Luminance (brightness). Remember just small changes.

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Once you have the colours how you want them then itâ&#x20AC;&#x2122;s time to address the noise. Go into filters and then into Reduce noise. This will open a new box and give you options for Strength, preserve details, reduce colour noise and sharpness. Just play around in here sliding the settings with the preview ticked. This will allow you watch the impact these changes have live on your image. Itâ&#x20AC;&#x2122;s better to apply just a small amount of noise reduction as we can add more later.

After adjusting the noise I like to sharpen the image very slightly by using Unsharp Mask. Again just play around in here and watch the impact your changes have. Ok so what if you want to make changes to a part of the image but not others? There are a couple of options open to you. The easiest is probably to select the part of the image you want to modify as in this picture by using the lasso tool. Once selected any changes you make in curves, levels etc will only be applied to this part of the image and the background sky will remain unchanged. If it was the sky that you wanted to make changes to select the galaxies as in the image and www.astronomy-wise.com

then invert the selection so now everything apart from the galaxies is selected. Now your changes will be applied to sky leaving the galaxies untouched. Another method would be to use layer masks but Iâ&#x20AC;&#x2122;ll leave that for a future episode as it starts getting a bit more involved. I think that is pretty much all the basics covered and you should be able to make significant improvements to your images. You can go back at any stage during the processing and tweak the levels, curves, add more noise reduction, up the vibrance etc. This really is just the basics and Iâ&#x20AC;&#x2122;m sure there are lots of different ways to achieve the same results. This is just the way I do it and I hope you have found it of some use. Before and after side by side

By Mike Greenham

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COMING SOON

Brief NeWsâ&#x20AC;Ś.. Astronomer Studies Far-Off Worlds Through 'Characterization by Proxy' A University of Washington astronomer is using Earth's interstellar neighbors to learn the nature of certain stars too far away to be directly measured or observed, and the planets they may host. Science Daily

A3 & A4 POSTERS Coming soon to Astronomy Wise quality printed posters. Images taken by Mike Greenham. Printed on quality paper you can own a piece of the universe

Mars One starts its search for the first humans on Mars NEW YORK, Monday, 22nd April 2013 Mars One is happy to announce the launch of its astronaut selection program today. The search has begun for the first humans to set foot on Mars and make it their home. Mars One invites would-be Mars settlers from anywhere in the world to submit an online application via apply.mars-one.com. Saturn's Rings Hit by Meteor Shower

Source: National Geographic

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Image by Mike Greenham www.astronomy-wise.com

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Holiday in Norway! By Leon Kijk in de Vegte

10-02-2013 was the day I went to Norway. (svolvaer) My dream vacation, was to see the northern lights. I had always dreamed of it and now the time was here. It was a short trip for 5 days. The weather looked good. So me and my Nikon d700 and my Nikko 14-24 lens went to Norway. At first night I woke up at 3am in the morning and went outside to see small stroke of vague green light. Disappointed cold I went to bed. The next day was different, I went to the polarlichtcente in laukvik, for a reading about the northern lights. And suddenly they said to go outside!!!! And there it was aurora everywhere. Some people danced, i was surprised how big it was. And forgot to take pictures. The next day the same aurora was everywhere, green some red jus great from 20.00 till 05.00, I took a lot of pictures, the cold weather was killing the battery life. I had six batteries, and all were used in one night. Itâ&#x20AC;&#x2122;s hard to get a really good picture for the first time. So I have to go back!!!!!

Here are a few pictures. if you want to see more of my aurora, astro pictures follow me on twitter @leonkidv or on facebook (leon kijk min de vegte) Editor: Thanks Leon for sharing your holiday. Leon is from the Netherlands and took is holiday in Norway, I look with envy at the photographs. All images: Leon Kijk in de Vegte

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NorWay ‘NortherN lights’ By Leon Kijk in de Vegte

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ASTRONOMY Recent Discoveries & Developments

From the Reviews: This book is packed with interesting new topics in easily readable chunks. No maths, just plenty of illustrations in glorious colour, sprinkled with explanations and anecdotes. An excellent read for kids and grown-ups alike, ideal for browsing on a journey. Can't wait for the next editionâ&#x20AC;Ś â&#x20AC;ŚMargarita

Although the lifetimes of stars and galaxies are played out over hundreds and thousands of millennia, the field of Astronomy itself is fast paced, with hardly a week going by without a new discovery or development hitting the headlines. This book delves into the most significant, ground breaking, headline making stories that have come out of Astronomy throughout 2011-12 and presents them in an easy to read, easy to understand format. The Perfect Introduction The Perfect Catch-up Available from Amazon in Kindle and Paperback Formats

For more information go to www.paulrumsby.com Facebook page: www.facebook.com/AstronomyRecentDiscoveriesAndDevelopments Follow the Author on Twitter @PMRumsby

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Paul Halperns new book â&#x20AC;&#x2DC;Edge of the Universeâ&#x20AC;&#x2122; A voyage to the cosmic horizon and beyond. The universe is a vast and complex place. It is full of mystery and wonder. We can peer out into the galaxy from our back gardens with small telescopes and see the stars and planets. However have you ever thought when gazing up how did this magnificent spectacle begin? How big is the universe? Is there more than one Universe?

Like you I have asked myself these and many more questions. Dr Paul Halpern who is an American Professor of Physics and a well publisher author may have the answers I am looking for. I downloaded the book onto my Galaxy Pad, using the Kindle app from amazon. Firstly the book is well laid out and easy to follow. It is not over complex and the beginner to Astronomy and those with an interest of the universe will quickly be absorbed into the pages. We soon learn that the universe is full of dark energy and dark matter. There are ideas on multi-universe and unseen dimensions. Download this book, buy this book in traditional form, which ever you choose get yourself comfortable and begin your journey to the cosmos. Astronomy Wise Rating 5/5

http://edgeofuniverse.com/

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Tycho's Supernova There are about eight supernovas which are written in historical records as viewed to the naked eye. Tycho's Supernova is one of them. One of the most important event in the history of Astronomy was the appearance of this supernova (which was called a "new star") in the Milky Way, in 1572. Its name is SN 1572. Astronomer Tycho Brahe published his own observatios and other's about this supernova ahd this is why it is called so. It's a Type Ia supernova. One of those occurs in binary system in which one of the stars is a white dwarf; they have a reliable bright. SN 1572 is located in Cassiopeia constellation and it is about 8,000 light years far away. What you can see in the image is the remnant of the supernova explosion. Red and green colors are due to low and medium energy X-rays. A beautiful shell of blue color covers the supernova. High energy X-rays are the resposible of that color. Also, you can see a short blue arc in the lower left region. Several details point to the fact that this arc is caused by an exploding white dwarf which blew material off the surface of the companion star. This material creates a shock wave in blue color as show. We can sey that this is an "historic" image (though it is taken nowadays) of an event which ancient astronomers could see. Science is always providing new answers to early questions.

Words: Pepe Gallardo Image Credit: NASA/CXC/SAO/P.Slane, et al.

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The Night Sky.. By John Harper F.R.A.S At the beginning of the month the Sun continues its journey through the constellation of Aries, until the 14th at around 06h, when it crosses the border into Taurus. In the northern parts of the UK, twilight begins to persist all night, and there are no truly dark nights until the end of July. From now on, look out for Noctilucent Clouds, which are thought to be produced as a result of meteors passing through the upper atmosphere. These thin high clouds of ice crystals still catch the light of the sun, which even at midnight is not far below the northern horizon. Their appearance is as silvery blue veils low in the northern sky, and may be seen an hour before and after midnight, often with interesting patterns.

The Moon The Moon is at perigee, the point of nearest approach to earth, at 01h45 on the 26th, and apogee, the furthest distance away from the earth as it can be, takes place at 13h31 on the 13th.

Last Quarter Moon is on the 2nd at 11h15 in western Aquarius, a couple of degrees above its border with Capricornus, and again on the 31st at 18h59 in eastern Aquarius approaching the Pisces border. New Moon is on the 10th at 00h29, when the moon passes just south of the sun in the constellation of Aries. At this time, residents of the northern parts of Australia witness an annular eclipse of the sun, the path of which travels eastwards across the Pacific Ocean just to the south of the Equator. First Quarter at 04h35 on the 18th near the intersection of the Leo, Hydra, and Sextans border, some 8° below and to the right of Regulus, Leo’s brightest star. Full Moon is on the 25th at 04h26 in the constellation of Scorpius close to the star Graffias (beta Scorpii), a 2.6 magnitude star in the area which marks the head of the scorpion. Because of the proximity of the bright moon, you will need a telescope to spot this star as the moon and Scorpius begin to set in the SW. There is a penumbral eclipse taking place, but nothing of it will be seen as the moon briefly grazes the penumbra of the earth’s shadow. This is one of the lowest full moons of the year. From the 12th to the 16th earthshine may be seen on the night hemisphere of the waxing crescent moon, when twilight fades sufficiently for this phenomenon to be seen.

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The Planets Towards the end of the second week of May, Mercury reappears in the evening twilight for its greatest eastern elongation next month. Despite the increasing twilight this is the second best evening apparition of the planet this year, after which there are no other suitable opportunities to observe Mercury in the evening sky until next year. Towards the end of the month, you should look for the planet low in the WNW twilight. At this time the planet is setting a good two hours after the sun. If you look low down in the NW quadrant of the sky at 21h on the 24th May, you ill be treated to the spectacle of Venus in conjunction with Mercury, with Jupiter near by. At this time, Mercury is 1° to the upper right of Venus, and 4° to the upper left of the pair is Jupiter. Pan the area with a pair of binoculars to locate these three planetary bodies, a truly delightful sight. Although Mercury is the dimmest member of the trio, it shines brighter than any of the stars with the exception (just) of Sirius. Venus continues to emerge as a glorious object in the early evening sky, setting 90 mins after the sun at the end of the month. As mentioned above it is a great assistance in locating fainter Mercury on the 24th. To the ancients, the planet, during its evening apparition, was known as Hesperus – the Evening Star. Although Mars is theoretically a morning object, rising before the sun, its low altitude and faintness in bright morning twilight, conspire to prevent the planet from being seen.

Jupiter, from setting three hours after the sun at the beginning of May, sets 30 mins after the sun by the end. The period available for observation of the planet decreases rapidly as the month progresses. However, don’t forget to look for the close approaches of Venus and Mercury to the giant planet, when on the 27th, Jupiter and Venus and Mercury form a small isosceles triangle with Mercury at the apex above the two brighter planets Jupiter and Venus. Look within 10° of the NW horizon at around 21h using binoculars to begin with, when you will see Jupiter just over 1° (two moon widths) to the left of Venus, with Mercury 2° above the pair. At 21h on the 12th, Jupiter and the two day old waxing crescent moon, form an interesting alignment, when they lie 10° above the horizon and separated by 5°, the planet lying just under 5° to the right of the lunar crescent. www.astronomy-wise.com

Saturn was in opposition at the end of April, and so is visible for most of the night as soon as the sky gets dark enough to see it. At the middle of May the planet crosses the Meridian some 25° above the south point of the horizon around 23h. The bright star 14° to the right of Saturn is Spica, the brightest star in Virgo, which was on the south Meridian an hour earlier. Half way between Saturn and the zenith (the point overhead) is Arcturus, the brightest star north of the in celestial equator. The planet’s rings are a beautiful sight in a small telescope, and it is worth noticing that the planet shines steadily whereas the two stars mentioned twinkle away merrily This is an effect due to the turbulent currents in the earth’s atmosphere, for the stars are mere points of light whereas the planet and its rings form in effect a small disc. Uranus rises shortly before 02h at the end of May, but increasing twilight interferes with attempts to observe this remote world, which is currently in the constellation of Pisces the Fishes near the border with Cetus the Whale, and rather low in the eastern sky. Similarly hampered by twilight persisting all night at the end of the month, distant Neptune, in Aquarius, three times fainter than Uranus, is unlikely to prove a satisfactory object to locate. If however you wish to try, you must use a star atlas or ‘Application’ to find the fifth magnitude star sigma Aquarii, and then finding the much fainter point of light 1° above and slightly to the left of sigma. That faint point of light is Neptune. If you look at the sky in the early morning of the 6th from 02h, you may see an increase in the number of shooting stars visible. Earth is crossing the path of Halley’s comet, and tiny particles, debris from this famous ‘dirty snowball’ hit the upper atmosphere as the Eta-Aquarid meteors. Constellations visible in the south around midnight, mid-month, are as follows: Libra, Scorpius, Serpens Caput (the serpent’s head) and Corona Borealis. All times are GMT

1° is one finger width at arm’s length.

Below May Lunar Occultations

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LETS TALK â&#x20AC;Śâ&#x20AC;Ś. INTERVIEW DR . CLAUDIA J. ALEXANDER This month Astronomy Wise magazine would like to welcome Dr Claudia J. Alexander to our pages. Claudia is the project manager for the Rosetta project.

Dr Claudia J. Alexander Project Scientist, U.S. Rosetta Project Jet Propulsion Laboratory

AW: Can you tell us a little about your role at NASA? CA: I am the Project Scientist for the NASA contribution to the International Rosetta Mission. That means that my 'jurisdiction' if you will, is the NASA instruments, interacting with the US media, and science experiments from US universities and research institutions. Not to mention interacting with NASA itself for funding and adjustments to NASA's portion of this mission. I am not the official project scientist for this ESA mission. Nonetheless, being part of a collaboration between NASA and ESA requires a certain skill set. One has to be sensitive to cultural differences, just as one does between cultural differences between say, JPL and Lockheed Martin, only on a much bigger scale.

AW: What is the Rosetta Project? CA: Rosetta is the European Space Agencies 3rd cornerstone mission. That means it is what we would call a flagship -style mission. It will have the biggest suite of instruments (including a lander) with which to explore a target that has ever been flown. The instruments (in my opinion) are some of the most capable, best instruments ever built. It will land on a comet, and then 'escort' the comet around the Sun for 17 months thereafter. Just the act of flying around an active comet will be extremely challenging. The mission will be the first to land on the surface of a comet. It will be technically challenging, and also an incredible opportunity to study a frozen remnant from the dawn of the solar system.

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AW: In your school years I have read you enjoyed engineering, what drew you to engineering? CA: I was blackmailed by my parents! Grins. I really wanted to write, and study political science/journalism (I would have been Gwen Ifill, of the PBS Newshour program. Your readers in the US will probably know who I mean.) But when I was growing up, black people weren't on TV, and that was not a career path that seemed viable to my parents. Neither was science, but they were willing to fund me to do engineering. We lived in the Silicon Valley of California. It seemed like a good move. 'Get a day job,' they said. Then when you have a steady income you can do whatever you like in your spare time. In retrospect, it was good advice. But it turns out I was much less turned on by engineering, where the problems — like building roads — seemed straightforward, as I was by science, where the problems — like how did the solar system form — seemed to require more 'outside the box' thinking. AW: How much were you parents a driving force in how you have developed and your career? CA: My parents pushed all through my formative years in public school to get me into college. They kept pushing on academics so that I could get into college. I don't think they had a vision for what would happen after college. In particular, they were really not keen on graduate school. When I stayed in school to get first a Master's Degree, and then a Ph. D., they accused me of being a perpetual student! They didn't understand what a research scientist was and did. I don't think my mother got it until I signed up to be an Adjunct Professor somewhere. She understood 'professor,' and I think that was the happiest I'd ever heard her on the phone about my career & prospects. Below: image source Wikipedia (link)

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AW: Can you tell us about your education, from your NASA profile it looks impressive. CJ: I have three degrees. That's not so unusual for a research scientist. I have a Bachelor of Arts degree in Geophysics from the University of California at Berkeley; a Master's Degree in Geophysics & Space Physics at UCLA; and a Ph.D. In 'Other' at the University of Michigan. (That's because 'space plasma physics' is too targeted a degree even from the Engineering Department at UM. Grins

AW: Life outside of Earth, where do you think we are likely to find it? And what sort of life do you think it may be? CA: I think life is everywhere. Or at least very common in the universe. It seems from looking at models, that it is more difficult to prevent life from forming, than to have life evolve. And by that I mean microbial life. I think we are still learning about life â&#x20AC;&#x201D; the difference, for example, between something living and a mineral. And we have a lot to learn about different kinds of chemical systems. Look at how life is able to survive/adapt in these extreme environments like so-called 'clean rooms.' That's why both the Mars missions and the Saturn/Titan missions are so interesting. Why would a planet like Mars be barren? The question of sophisticated, intelligent, multi-cellular life, is different. It might be extremely rare, and also extremely difficult to communicate with (if outside out solar system). The distances are vast compared to our lifetime. Another consideration. Life on Earth has gone through 3-4 major crisis over geologic time, crisis that forced/shaped living beings to be as we know them today â&#x20AC;&#x201D; for example, oxygen used to be toxic to life. That would be expected given that oxygen is a radical (why we worry about 'anti-oxidants' today in our diet). But eons ago, as oxygen built up in the atmosphere, life adapted and learned respiration. In a different system, life may not have been forced to adapt that way. Photosynthesis was another major adaptation that allowed life to flourish. But the enzymes that allow photosynthesis are keyed to the particular energy of our Sun. So finding life elsewhere may have a lot to do with us learning more about how the universe works, and dropping pre-conceived notions about 'life as we know it.' AW: Did you get to observe the PAN STARRS comet? If yes how did it make you feel? CA: I have only seen pictures on astronomy websites. I am not an observer (I don't use a telescope for my science, I use equations to solve physical problems), but the sight of an object like PAN STARRS in the sky, like the beautiful comet McNaught, is www.astronomy-wise.com

awe-inspiring. Makes you feel small, and contemplate the vastness of regions beyond Earth. Sort of like the site of the aurora — particles falling through the Earth's atmosphere as if a giant searchlight were shining down from on high. Hard to conceptualize that the atmosphere goes up that far! Much less that when you see the beautiful vision of a comet outgassing as it goes around the Sun that it is millions of km away. AW: Space Travel, how far away is a human mars mission? CA: Grins. I should think 100 years away. I usually tell kids that it's their generations technical challenge. But I don't see it happening in the next 25 years. It's a huge challenge to lift human beings into space, much less have enough 'umph' to carry them to Mars with all the life support equipment that would be required to sustain them for the length of time they would want to be there. It would have to be done piecemeal, with robots to create a base that was sustainable. You would want to practice that on the Moon. The question of 'why' would have to be answered… why can't Mars exploration not be done robotically? Why does a Human have to go to Mars. I'm not sure the political world is ready, right now, for a non-practical answer to that question, given looming social/financial/climate issues on Earth. Going to the Moon was … 'Because it was had…" to coin a phrase, meaning that it was just barely within our technical resources at the time and we needed to prove to ourselves that we could do it. The political impetus ran out after that initial proof was done. But Human entrepreneurs have been known to succeed where governments have lacked the will in the past. AW: Comets, what has the project learnt about them CA: Rosetta won't emerge from hibernation until early next year. And the landing won't happen for another 11 months after that [November, 2014], so we have a ways to go. But I suspect we're going to be just as turned around as we were on Galileo between what we knew when the spacecraft arrived for its mission, and what we knew by the time we crashed it (on purpose) into the atmosphere. Epoxi & NeXT have given us tantalizing clues about www.astronomy-wise.com

the big learning curve we have ahead of us on comets. For decades we've described them as frozen time capsules from the dawn of the solar system, but NeXT imaged a surface with obvious geology, with features that are short-lived (over geologic time, that is) -- features that obviously weren't part of a 'frozen time capsule' but that show recent evidence of change. At the same time there was evidence that change didn't happen the way we expected. The comet target of NeXT (Tempel 1 was the target of the 2004 Deep Impact mission, which blew a hole in the supposed crust of the nucleus) showed absolutely no change in the cavity that was created with the Deep Impact missile. That was a complete surprise. If it were made of ice (water ice) it should have behaved like we expect ice to behave. And so now we are scratching our heads wondering just what are these crazy things called 'comets'? AW: What do you feel are your greatest achievements CA: (E) In the community where I grew up, giving back to the community you came from is an important marker of accomplishment. In that regard, I've been delighted to be part of several successful collaborations on education. One is on the Navajo reservation. Another has been working with television producers over the years to create accessible material for science. Another hopefully will be the science-learning (STEM) children's book series. Sort of my vision of the solar system, conveying a sense of its wonder to a new audience.

AW: Can you tell us about your books, Windows to Adventure CA: Windows to Adventure is a series of sciencelearning (STEM education) books for ages 8-10. The kids go through a magical 'window' into a place where they can explore planets & stars. The stories have a fantasy element & loads of art; talking mountains and alien creatures. I'm publishing them myself, after spending a lot of time unsuccessfully seeking a publisher. The first will roll out in July (hopefully). They'll be done in Spanish & French. We'll see how that goes. The lead character, Angie Coradini, was named after a colleague, Dr. Angioletta Coradini, who was one of the premier female European planetary scientists. Some of my other colleagues have graciously donated forewords for one or more books in the series. The germination of the books was back ten years ago with the collaboration on the science-learning website Windows to the Universe. That site was written at three different reading levels, elementary school, middle-school, and high school reading www.astronomy-wise.com

levels. We kept getting requests from parents for something more engaging for the youngest reading level. The leader of this project didn't want to try anything with fantasy — no talking mountains! I wanted to try making science more accessible with humor, fantasy, and artwork — real art. The sticky point is that no publisher will put that much art into a chapter book for kids. Kids are reading by age of 8-10, and should have fairly large vocabulary, so why go to the expense of pictures? My thinking was that for science-learning, you really need art, to convey the meaning of the words/concepts. And in the case of geography and/or planets & astronomical phenomenology, to convey a sense of wonder. Turns out that not everyone who looks at a landscape sees something beautiful or majestic. Sometimes when people look at a lawn, they just see dull grass. They can't even distinguish rye grass from St Augustine's! Even with my artists, getting them to convey the majesty of a particular mountain range, or tropospheric storm – to convey the lawn instead of the grass … took a lot of work. I'm hoping that the books will find an audience — that the work to visualize the majesty of Earth & space will be appreciated! Grins. A big thank you to Claudia for taking the time to talk to us, please visit the links Below, all links have live linking. Credits: book covers– Red Phoenix Books : NASA JPL– NASA : Red Phenix Books banner

USEFUL LINKS NASA JPL ESA ROSETTA Windows to Adventure Red Phoenix Books

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When Stars Die by Julian Onions So we’ve seen how stars live, and how they can extend their lives by switching to helium, an available but less efficient forms of fuel. Why is helium less efficient? Well the secret is in the graph below.

Graph Below: Graph of binding energy

The Y axis is the amount of energy for each particle in the nucleus. You can see hydrogen way down the bottom, and helium at just over 7000 (the units are keV but it doesn’t really matter). What is important is the difference in levels. So from H to He we get lots of energy released - over 7000 units. From He to C, not very much in comparison, maybe a few hundred. So it’s no wonder hydrogen is the preferred fuel. There are other elements that can be “burnt”, carbon (C) to oxygen (O), to Neon (Ne), magnesium (Mg), and silicon (Si), and to Iron (Fe) however from the graph it’s clearly not very efficient. After iron (Fe), you can see the graph goes down. So to make anything after iron you have to put energy in. You can go the other way - from big nuclei to small ones, and things beyond lead (Pb) like uranium, you can split up, and make energy. This is what atomic power stations use. You can see compared to the H->He jump, it’s also pretty inefficient. So burning hydrogen to helium is the best bang for the nucleus, helium to carbon is the next best, but not nearly as good. After that there are more exotic www.astronomy-wise.com

schemes. Burning two carbons to neon, or making oxygen (C+He) or magnesium are all options. Hotter temperatures allow neon burning and oxygen burning producing silicon. This is an increasingly desperate rush for burning whatever is available. Itâ&#x20AC;&#x2122;s like starting with a nice big wood pile, and then having to burn the chairs and table, and finally the house to keep warm. Carbon burning, for instance, will typically give the star extra burning time of a few hundred years, contrasting with millions or billions of years for hydrogen burning. Oxygen/neon burning is only good for a few months to a year to support the star against gravitational collapse. In the final phase, it can burn silicon, but its clear from the graph above, there is very little energy available from this. Silicon burning, which is only available to the very biggest stars, and requires temperatures around 2-3 billion degrees, can only keep the star going for a matter of hours or days. Typically a star in this late stage of its life can be doing several types of burning at once, in shells Image: Shell burning in a massive star In this mode of extended shell burning, large solar winds are generated, and a lot of mass is emitted from the star as it swells up and the outer surface becomes very tenuous. Eventually - there is nothing else left to burn, or at least not enough to keep up the mass of material that makes a star. Itâ&#x20AC;&#x2122;s like a weightlifter, holding a weight above his head. Sooner or later their arms will give and it will all come crashing down. So what happens next? It depends on how massive the star is. Stars the size of our Sun and

less just slowly collapse in on themselves. In the case of our Sun the core will be mostly carbon with perhaps some oxygen. The Sun will shrink until it is about the same size as the earth. It will still be very hot, but no longer burning. Known as a white dwarf (not to be confused with a red dwarf, the type of star or the tv show), it will sit there glowing for billions of years slowly cooling down. The structure will be compressed into degenerate matter, which is how you get a suns worth of mass into something the size of the Earth. Carbonâ&#x20AC;&#x2122;s most compact form is diamond, so we will end up with one very large, very hot diamond. Oddly enough, the more matter you put into a white dwarf, the smaller it gets - such is the odd nature of degenerate matter. It is a very dense state of matter, and prevented from collapsing further only by the degeneracy pressure of electrons pushing back.

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Theoretically it will then eventually turn into a black dwarf (not to be confused with a brown dwarf) - that is a white dwarf that is so cool it no longer even glows. However as this takes longer than the lifetime of the universe, no star has yet got into this state. Anything bigger than about 1.4 times the mass of our Sun at the end of its life (and stars lose a lot of mass in their later stages) are too massive for the degenerate material to resist the collapse. In this case the electrons are squeezed further, and combine with protons to form neutrons. This neutron pressure can resist the squash, up to about 3 solar masses worth. The subsequent neutron star is very dense and very small. Maybe 10 km across, the size of a not particularly big city. Impression of a neutron star wikipedia

Neutron stars have an impressive density, often quoted in various ways such as - a grain of neutron star ‘sand’ weighs the same as a 747. Although no one has done the experiment - I suspect if you had a grain of neutron star material on it’s own, it would quickly expand back to its original size! If the remains are bigger than somewhere in the 3-5 solar mass range, we run out of resistant forces. The star collapses in on itself, becoming that most famous of weird objects - the black hole. They are famous in science fiction and certainly have a few freaky properties, such as being so massive that even light can’t move fast enough to escape them. However they are not the cosmological hoovers that they are sometimes portrayed. Sure if something comes close enough it will get sucked into it, never to be seen, but the same will happen with our Sun. The black hole has less “sucking” power than the star it formed from, as “suckiness” is the gravitational field it generates, which is dependant on it’s mass. The mass of the black hole is usually quite a lot less than the star that formed it, as there is a lot of material lost in the formation process. If we converted our Sun into a black hole, the Earth would carry on going around in orbit unchanged. www.astronomy-wise.com

Of course it wouldnâ&#x20AC;&#x2122;t shine so it would get awfully cold and dark, but we wouldnâ&#x20AC;&#x2122;t get sucked into it suddenly.

[ http://upload.wikimedia.org/wikipedia/commons/thumb/5/5e/BH_LMC.png/600pxBH_LMC.png Artists impression of a black hole - distorting space and everything!] The death throws of these huge stars are the subject of the next article, and are quite the most spectacular of events.

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DAYSTAR SOLAR SCOPES With the summer months fast approaching now is a good time to look at our nearest star the sun. There are many ways to view the sun, from white filter film and filters, Hydrogen Alpha or Calcium K to name a few.

â&#x20AC;&#x153;When viewing the sun you must always do so using the correct equipment and for those who are a novice go along to your local club for help and advice, never look at the sun directly without suitable Equipmentâ&#x20AC;?.

In the UK many of us a familiar with other branded solar scopes (PST) however there is a company in the USA who produce their own brand of solar scopes. The company is DAYSTAR. In the UK you can purchase an 80mm version of the scope. However I am told that there is a 127mm scope due out. The 80mm scope ranges in price depending on the bandwith you require from $3500 to $9000. Unfortunately we were unable to test out the telescope, however we will try to have a look at one in the future.

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All images from DAYSTAR

So what we have done is made available the specification details of the 80mm Version for more detail please go to http://www.daystarfilters.com Full 80mm Aperture offers high resolution views. 2" dual speed Crayford Style Focuser. Includes White Light Solar Finder Scope. NEW! Focal reducer diagonal offers eye-popping views! Electronic Tuning assures on band performance Superior ION baffling enhances contrast. Same DayStar Trade-in / Upgrade Policy 5 Year Warranty

Specifications: Clear Aperture: 80mm Focal Length: 2280mm strait through / 1140mm through .5x diagonal Limiting Resolution: 2.06 Arcseconds Telescope Length: 42" Telescope Weight: 8lbs, 2 oz Operating Temperature: 20-100Â° F Power supply: DC 12V, maximum 120mA, 2.1x5.5mm AC Adapter included: 120-240VAC Power consumption: 1.5 watts Wavelength Shift range: 1Ă&#x2026; 100% safe and fully blocked directly through the OTA Reaches focus using the following: 1.25" eyepiece, 2" eyepiece, ToUCam, Lumenera, SBIG, SLR, DSLR*, afocal, CCTV Video, 2X - 5X Barlow lenses with any combination included above. Includes: Complete Hydrogen alpha Solar Telescope 2" dual speed Crayford style Focuser DayStar custom .5X focal reducing visual diagonal 20mm plossl eyepiece 2" to 1.25" Drawtube reduction adapter Solar Finder Scope fitted with Thousand Oaks white light solar filter Felt lined mounting rings Vixen Style Dovetail mount 12VDC Power supply with International wall adapter plug 6 foot (1 meter) power extension cord Custom fitted pelican style wheeled travel and storage case. Performance engineered for flexibility, the SolaREDi has been rigorously tested for ease of operation, function, reliability and adaptability with various cameras.

http://www.daystarfilters.com www.astronomy-wise.com

Astronomy Wise is always looking for something new. Here we have an artist from Budapest who's art takes a science and astronomy view point.

Exhibitions:

2009 Budapest , Bakelit Multi Art Center, Diploma Nélkül II. 2010 Budapest, Pszinapszis XIV. 2012 Érd, City Gallery, Ez van! 2012 Budapest, Syma Centre, Decoration Society Contest II. 2012 Budapest. FN5, Millenáris 2012 Vác, Exhibition of the Contemporary Values II. K.É.K. 2012 Budapest, Bakelit Multi Art Center 2012 Budapest, Abszurd Flikk-Flakk, Alle Center 2012 Budapest, Bakelit Pályázat 2nd Exhibition, Fogasház Kulturális Befogadótér 2012 Budapest, Honoratus Kodály Zoltán, MOM Kulturális Központ 2013 Los Angeles, NAMM Show / Fibenare Upcoming shows/Events: Guitar Connoiseur Magazine New York – next issue cover (www.guitarconnoisseur.com ) 12th April – 20th August Budapest Art Expo Friss 2013 MűvészetMalom, Szentendre

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SATURN As we move into the summer months we enter a period of lighter nights. This makes viewing deep sky objects more difficult. However for the amateur astronomer there is a celestial body which fills us with awe. This wonder of the solar system was the first object that I viewed through a telescope. And I must admit I was blown away. This celestial body is Saturn. Saturn sits in the outer reaches of the solar system; it is a huge gas giant. Saturn is the sixth planet from our star (the sun); it has a ring system and many moons.

Photo: Saturn taken by the Cassini probe (NASA/JPL/Space Science Institute)

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Composition of Saturn Saturn as mentioned before is what we call a gas giant, composing of mostly hydrogen (H) 88%*, Helium (He) 11%* with trace elements of water, methane and ammonia. Its outer layers are that of gas, however as you move towards the centre the gas becomes denser eventually forming a metallic mantle of hydrogen and helium. This metallic structure is a good electrical conductor and the electrical currents formed possibly by fast moving molecules creates electrical currents which are possibly responsible for the planets magnetic field. Note: * % content differ from different sources.

The core may contain heavier elements and its structure is icy and rocky. What is interesting is that both Saturn and Jupiter are still evolving, they are still settling in gravitational terms. This means they are contracting which in turn created internal heat. Saturn radiates 3 times more heat than it receives from the sun.

history? And is it possible they will become smaller and denser in their future? Saturn has some of the fastest winds in the solar system; storm clouds on the equator have rotated around the planet in just over 10 hrs giving wind velocities of 1700 Km/h

Could it be possible the gas giants were a lot bigger in their early www.astronomy-wise.com

The Rings Saturnâ&#x20AC;&#x2122;s rings can be seen with a small telescope; however larger telescopes give you more detail. The rings are amazing to see. With a smaller telescope the rings appear more as one ring, larger scopes you can make out in more detail individual rings. The rings have been identified and labelled in order of discovery and using a simple identification system, (A,B,C to G). The rings are mainly composed of water ice; they range from small particles to larger lumps. Some of the material in the ring is rocky however this is mainly trace elements.

Other planets have ring systems however Saturnâ&#x20AC;&#x2122;s are the most stunning. We have found the rings vary in density and there are gaps in the system, we have also discovered moons embedded into the system.

How were they formed? There are two main theories on how the rings were formed. One theory is that a moon moved inwards during its orbit, the tidal forces of Saturn ripped the moon apart and created the ring system. Theory two is that the ring system are the remains or left overâ&#x20AC;&#x2122;s from nebular material from which Saturn was formed. Other theories include a moon collision.

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The densest parts of the ring system are the A and B rings. There is a gap in between the rings called the Cassini division. This was discovered by Giovanni Domenico Cassini in 1675. The C ring which makes up the main three rings was discovered in 1850. The main rings contain larger particles. The other rings D,E,F,G can be described as dusty rings and are not as dense as the main three. D ring inner most very faint C ring wide and faint B ring largest and brightest of the rings A ring outer most of the large bright rings, its inner boundary is the Cassini division. F outer most ring, and the most active. Its features change hourly.

Giovanni Domenico Cassini June 8, 1625 Also known as Gian Domenico Cassini or Jean-Dominique Cassin

Janus/Epimetheus ring faint dusty ring, the moons Janus and Epimetheus orbit in this ring. Material in this ring is ejected material from the moons; this would have been caused by impacts. G ring very thin ring and faint, positioned half way in between the F and the beginning of the E ring, its inner edges is in the orbit of the moon Mimas Methone Ring Arc faint ring discovered in September 2006, the moon Methone orbits within this ring Anthe ring faint ring discovered in 2007 Pallene ring a faint dust ring E ring, second most outer ring and is very wide. It starts at the orbit of Mimas and ends a Rhea. It consist of ices, silicates, carbon dioxide and ammonia. The particles are mainly microscopic. Phoebe Ring in Oct 2009 the rings discovery was announced, it is just in the orbital plane of the moon phoebe.

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Moons So far 62 moons have been discovered and 53 have been named, the largest being Titan. The moons themselves are different from moon to moon; one of the more interesting moon s is the second largest in the solar system, Titan. This moon is the only other place apart from Earth where a liquid freely flows on the surface.

“Saturn’s largest moon titan, covered in a thick atmosphere. Titan is the only other body apart from Earth where a liquid flows on its surface”. Words: David Bood Images: NASA, Wikipedia Sources: NASA, Wikipedia

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AR CLUSTERS

M13 globular cluster Image: Mike Greenham There are two types of star cluster, open and globular. Open clusters are more loosely clustered stars and usually contain fewer stars than their globular counterparts. Over time giant molecular clouds can have gravitational influence over the cluster. Generally the stars in these type of clusters are younf stars.

Globular Clusters These are large groupings of stars, they appear spherical. Their numbers can range from 10,000 to several Millions in a 10 to 30 million light year area. These clusters are old or older stars and may be only a few million years younger than the universe itself.

â&#x20AC;&#x153;A light-year is a unit of distance. It is the distance that light can travel in one year. Light moves at a velocity of about 300,000 kilometers (km) each second. So in one year, it can travel about 10 trillion km. More p recisely, one lightyear is equal to 9,500,000,000,000 M80 GLOBULAR CLUSTER Image: Wikipedia

kilometresâ&#x20AC;?. (NASA)

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Pleiades â&#x20AC;&#x153;Seven Sistersâ&#x20AC;? open cluster, this is an amazing object to view in the winter months Words: David Bood Images: Mike Greenham, NASA, Stellarium

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Henna Khan : Partial Lunar Eclipse www.astronomy-wise.com