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Taken By Michael. J. Melwiki . Taken with Iphone 5s 10 inch f6 Taken from Michigan United States of America
By California Institute of Technology,
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Caltech researchers have found evidence of a giant planet tracing a bizarre, highly elongated orbit in the distant solar system. The object, which the researchers have nicknamed Planet Nine, has a mass about 10 times that of Earth and orbits about 20 times farther from the Sun on average than does Neptune (which orbits the Sun at an average distance of 2.8 billion miles). In fact, it would take this new planet between 10,000 and 20,000 years to make just one full orbit around the Sun. The researchers, Konstantin Batygin and Mike Brown, discovered the planet’s existence through mathematical modeling and computer simulations but have not yet observed the object directly. “This would be a real ninth planet,” says Brown, the Richard and Barbara Rosenberg Professor of Planetary Astronomy. “There have only been two true planets discovered since ancient times, and this would be a third. It’s a pretty substantial chunk of our solar system that’s still out there to be found, which is pretty exciting.” Brown notes that the putative ninth planet -- at 5,000 times the mass of Pluto -- is sufficiently large that there should be no debate about whether it is a true planet. Unlike the class of smaller objects now known as dwarf planets, Planet Nine gravitationally dominates its neighborhood of the solar system. In fact, it dominates a region larger than any of the other known planets -- a fact that Brown says makes it “the most planet-y of the planets in the whole
Batygin and Brown describe their work in the current issue of the Astronomical Journal and show how Planet Nine helps explain a number of mysterious features of the field of icy objects and debris beyond Neptune known as the Kuiper Belt. “Although we were initially quite skeptical that this planet could exist, as we continued to investigate its orbit and what it would mean for the outer solar system, we become increasingly convinced that it is out there,” says Batygin, an assistant professor of planetary science. “For the first time in over 150 years, there is solid evidence that the solar system’s planetary census is incomplete.” The road to the theoretical discovery was not straightforward. In 2014, a former postdoc of Brown’s, Chad Trujillo, and his colleague Scott Shepherd published a paper noting that 13 of the most distant objects in the Kuiper Belt are similar with respect to an obscure orbital feature. To explain that similarity, they suggested the possible presence of a small planet. Brown thought the planet solution was unlikely, but his interest was piqued. He took the problem down the hall to Batygin, and the two started what became a year-and-a-half-long collaboration to investigate the distant objects. As an observer and a theorist, respectively, the researchers approached the work from very different perspectives -- Brown as someone who looks at the sky and tries to anchor everything in the context of what can be seen, and Batygin as someone who puts himself within the context of dynamics, considering how things might work from a physics standpoint. Those differences allowed the researchers to challenge each other’s ideas and to consider new possibilities. “I would bring in some of these observational aspects; he would
Fairly quickly Batygin and Brown realized that the six most distant objects from Trujillo and Shepherd’s original collection all follow elliptical orbits that point in the same direction in physical space. That is particularly surprising because the outermost points of their orbits move around the solar system, and they travel at different rates. “It’s almost like having six hands on a clock all moving at different rates, and when you happen to look up, they’re all in exactly the same place,” says Brown. The odds of having that happen are something like 1 in 100, he says. But on top of that, the orbits of the six objects are also all tilted in the same way -- pointing about 30 degrees downward in the same direction relative to the plane of the eight known planets. The probability of that happening is about 0.007 percent. “Basically it shouldn’t happen randomly,” Brown says. “So we thought something else must be shaping these orbits.” The first possibility they investigated was that perhaps there are enough distant Kuiper Belt objects -- some of which have not yet been discovered -- to exert the gravity needed to keep that subpopulation clustered together. The researchers quickly ruled this out when it turned out that such a scenario would require the Kuiper Belt to have about 100 times the mass it has today. That left them with the idea of a planet. Their first instinct was to run simulations involving a planet in a distant orbit that encircled the orbits of the six Kuiper Belt objects, acting like a giant lasso to wrangle them into their alignment. Batygin says that almost works but does not provide the observed eccentricities precisely. “Close, but no cigar,” he says. Then, effectively by accident, Batygin and Brown noticed that if they ran their simulations with a massive planet in an anti-aligned orbit -- an orbit in which the planet’s closest approach to the Sun, or perihelion, is 180 degrees across from the perihelion of all the other objects and known planets -- the distant Kuiper Belt objects in the simulation assumed the alignment that is actually observed. “Your natural response is, ‘This orbital geometry can’t be right. This can’t be stable over the long term because, after all, this would cause the planet and these objects to meet and eventually collide,’” says Batygin. But through a mechanism known as mean-motion resonance, the anti-aligned orbit of the ninth planet actually prevents the Kuiper Belt objects from colliding with it and keeps them aligned. As orbiting objects approach each other they exchange energy. So, for example, for every four orbits Planet Nine makes, a distant Kuiper Belt object might complete nine orbits. They never collide. Instead, like a parent maintaining the arc of a child on a swing with periodic pushes, Planet Nine nudges the orbits of distant Kuiper Belt objects such that their configuration with relation to the planet is preserved. “Still, I was very skeptical,” says Batygin. “I had never seen anything like this in celestial mechanics.”
But little by little, as the researchers investigated additional features and consequences of the model, they became persuaded. “A good theory should not only explain things that you set out to explain. It should hopefully explain things that you didn’t set out to explain and make predictions that are testable,” says Batygin. And indeed Planet Nine’s existence helps explain more than just the alignment of the distant Kuiper Belt objects. It also provides an explanation for the mysterious orbits that two of them trace. The first of those objects, dubbed Sedna, was discovered by Brown in 2003. Unlike standard-variety Kuiper Belt objects, which get gravitationally “kicked out” by Neptune and then return back to it, Sedna never gets very close to Neptune. A second object like Sedna, known as 2012 VP113, was announced by Trujillo and Shepherd in 2014. Batygin and Brown found that the presence of Planet Nine in its proposed orbit naturally produces Sedna-like objects by taking a standard Kuiper Belt object and slowly pulling it away into an orbit less connected to Neptune. But the real kicker for the researchers was the fact that their simulations also predicted that there would be objects in the Kuiper Belt on orbits inclined perpendicularly to the plane of the planets. Batygin kept finding evidence for these in his simulations and took them to Brown. “Suddenly I realized there are objects like that,” recalls Brown. In the last three years, observers have identified four objects tracing orbits roughly along one perpendicular line from Neptune and one object along another. “We plotted up the positions of those objects and their orbits, and they matched the simulations exactly,” says Brown. “When we found that, my jaw sort of hit the floor.” “When the simulation aligned the distant Kuiper Belt objects and created objects like Sedna, we thought this is kind of awesome -- you kill two birds with one stone,” says Batygin. “But with the existence of the planet also explaining these perpendicular orbits, not only do you kill two birds, you also take down a bird that you didn’t realize was sitting in a nearby tree.” Where did Planet Nine come from and how did it end up in the outer solar system? Scientists have long believed that the early solar system began with four planetary cores that went on to grab all of the gas around them, forming the four gas planets -- Jupiter, Saturn, Uranus, and Neptune. Over time, collisions and ejections shaped them and moved them out to their present locations. “But there is no reason that there could not have been five cores, rather than four,” says Brown. Planet Nine could represent that fifth core, and if it got too close to Jupiter or Saturn, it could have been ejected into its distant, eccentric orbit.
Batygin and Brown continue to refine their simulations and learn more about the planet’s orbit and its influence on the distant solar system. Meanwhile, Brown and other colleagues have begun searching the skies for Planet Nine. Only the planet’s rough orbit is known, not the precise location of the planet on that elliptical path. If the planet happens to be close to its perihelion, Brown says, astronomers should be able to spot it in images captured by previous surveys. If it is in the most distant part of its orbit, the world’s largest telescopes -- such as the twin 10-meter telescopes at the W. M. Keck Observatory and the Subaru Telescope, all on Maunakea in Hawaii -- will be needed to see it. If, however, Planet Nine is now located anywhere in between, many telescopes have a shot at finding it. “I would love to find it,” says Brown. “But I’d also be perfectly happy if someone else found it. That is why we’re publishing this paper. We hope that other people are going to get inspired and start searching.” In terms of understanding more about the solar system’s context in the rest of the universe, Batygin says that in a couple of ways, this ninth planet that seems like such an oddball to us would actually make our solar system more similar to the other planetary systems that astronomers are finding around other stars. First, most of the planets around other Sun-like stars have no single orbital range -- that is, some orbit extremely close to their host stars while others follow exceptionally distant orbits. Second, the most common planets around other stars range between 1 and 10 Earth-masses.
“One of the most startling discoveries about other planetary systems has been that the most common type of planet out there has a mass between that of Earth and that of Neptune,” says Batygin. “Until now, we’ve thought that the solar system was lacking in this most common type of planet. Maybe we’re more normal after all.” Brown, well known for the significant role he played in the demotion of Pluto from a planet to a dwarf planet adds, “All those people who are mad that Pluto is no longer a planet can be thrilled to know that there is a real planet out there still to be found,” he says. “Now we can go and find this planet and make the solar system have nine planets once again.” Source - Astronomy Now
ALMA witnesses the birth of a triple-star system By, University of Oklahoma
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���� ������-���� ������ surrounded by a disc with a spiral structure has been discovered by a University of Oklahoma-led research team. Recent observations from the Atacama Large Millimetre/submillimetre Array — a revolutionary observatory in northern Chile, commonly known as ALMA — resulted in the discovery, lending support for evidence of disc fragmentation — a process leading to the formation of young binary and multiple star systems. Until ALMA, no one had observed a tri-star system forming in a disc like the one discovered by the OU team.
John J. Tobin, professor of astrophysics in the Homer L. Dodge Department of Physics and Astronomy, OU College of Arts and Sciences, led a global team of researchers who demonstrated that the disc surrounding the tri-star system appeared susceptible to disc fragmentation. Team members represented Leiden University, The Netherlands; University of Arizona; Chalmers University of Technology, Onsala Sweden; University of Illinois; SUNY Fredonia; University of Virginia; National Radio Astronomy Observatory, New Mexico; Max-Planck, Germany; and University of California, San Diego. Their research has just been published in the journal Nature. “What is important is that we discovered that companion stars can form in disc material surrounding a dominant star,” said Tobin. “We had observed this system in the past with ALMA’s predecessors, but this is the first time we have been able to clearly analyse the disc and the newborn stars within it. ALMA revealed the spiral arms and disc that led to the formation of the tri-star system. Triple systems like this one are rare, and this is the only one with a configuration like this, but we are actively searching for more.” How binary stars form has been a mystery for some time, and there are different theories about how they form — one is the fragmentation of the disc around the stars that are forming. Tobin explains the formation of the disc in which the tri-star system is forming is like a figure skater doing a spin and pulls his or her arms in to gather speed. A star initially forms from a cloud of interstellar gas that is collapsing under its own gravity. The spin from the cloud causes a disc to form as the material spins faster and falls toward the star. If the disc happens to have enough material, spiral arms form and the disc can fragment to another star. Source - Astronomy Now
Annie Jump Cannon - Astronomer Biography Annie Jump Cannon was a pioneering astronomer responsible for the classification of hundreds of thousands of stars. Synopsis Born on December 11, 1863, in Dover, Delaware, Annie Jump Cannon studied physics and astronomy at Wellesley College and went on to work at Harvard Observatory. A trailblazer for women in science, she discovered hundreds of variable stars and devised a
Early Life Annie Jump Cannon was born on December 11, 1863, in Dover, Delaware. Her father, Wilson Cannon, was a state senator, while her mother, Mary Jump, taught Annie the constellations at a young age and ignited her interest in the stars. Cannon attended Wellesley College, where she studied physics and astronomy. She graduated in 1884 and went on to focus on astronomy for two years at Radcliffe College.
Harvard Observatory Work In 1896, Cannon was hired as an assistant to the staff at Harvard Observatory under E. C. Pickering. Her hourly rate was 50 cents. In her position, Cannon joined a group of female astronomers nicknamed "Pickering's Women." The team, which included Williamina P. S. Fleming, worked to document and empirically classify stars. Cannon's role in the large-scale project was to study bright southern hemisphere stars.
Honors and Awards Cannon received honorary degrees from the University of Delaware, Oglethorpe University and Mount Holyoke College. She was the first woman to receive an honorary doctorate from the University of Oxford in 1925. She received the Henry Draper Gold Metal of the National Academy of Sciences. Cannon was also the first woman to hold an officer position in the American Astronomical Society. The organization still awards the honor Cannon established, the Annie J. Cannon Award. The prize is given to a distinguished woman astronomer at the beginning of her career. Cannon retired in 1940. She died on April 13, 1941, in Cambridge, Massachusetts.
Creating a Spectral Classification System As she began working, Cannon found the conventional systems of classification to be ineffective for her purposes. She combined two known models to create her own spectral division, the simplified classes O, B, A, F, G, K, M. The system was adopted as the universal standard and given the mnemonic device "Oh, Be A Fine Girl--Kiss Me!" which was utilized by astronomers for generations. Cannon was known for her diligence and skill in addition to her enthusiasm and patience. She classified more than 225,000 stars, and her work was published in the Henry Draper Catalogue over the course of nine volumes between 1881 and 1924. In 1911, Cannon became the curator of astronomical photographs at Harvard Observatory. She worked at astounding efficiency and was able to classify up to three stars a minute. In the 1920s, Cannon cataloged several hundred thousand stars to the 11th magnitude. She discovered 300 variable stars, in addition to 5 novae, a class of exploding stars.
The Online Astronomy Society Academy now run’s their own in house course the Diploma Astrophysics and space science. Between ourselves and Dr Nigel Marshall, we have long believed there was a need for an “A-Level” course. We say A-Level in inverted commas as it is targeted at that level, BUT there is no assessment, no final examination. Therefore NO final qualification is awarded. Despite this we feel the course will be more than worthwhile to follow. Not only to satisfy the hunger for knowledge from the more academic amateur Astronomer come Astrophysicist but to cater for the curious. This course endeavours to take you to worlds you have never been This is Available to £140
The Online Astronomy Society Academy also runs the GCSE in Astronomy which can be completed by Distance learning. It is credited by Edexcel. This course is now available for £180
Why Does Uranus Spin The Wrong Way?
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All the planets in our solar system spin from West to East, apart from Venus and Uranus. Scientists have known this for a very long time but they could never concretely explain why. Uranus has an especially peculiar movement as it practically spins on its side and Venus spins in completely the opposite direction to us. Given that all the planets were created in similar ways, they should all spin the same way, in theory of course. The belief is that the solar system was formed by the destruction and chaos in rotating gas clouds, which the planets, such as Earth, carried over and continued. Venus and Uranus, however, had other ideas and spin in what is known as a retrograde rotation, or opposite to the direction of the sun.
The most common theory when it comes to retrograde rotation states that something must have collided with both Venus and Uranus at some point in history to have caused the odd behavior. To cause the change of Venus is named after the Roman goddess of love and direction, the impact must have been enormous and beauty, but it’s actually a really weird place, proven probably involved planet sized objects. Others have by the fact that a single day on Venus actually takes suggested that Uranus may have once had an longer than a year on Venus. Venus is also weirdly enormous moon that dragged its planet down with its the only planet to spin completely clockwise. Uranus gravitational pull; a bit like a needy younger brother is just as weird as it spins on its side. This movement dragging you back. Some suggested it could have is known as retrograde rotation and has puzzled scien- been a series of smaller collisions that caused the rotations. tists for many years. It is thought that Venus once rotated like the rest of William Herschel first observed Uranuson 13 March us, counter-clockwise, but then slowed, stopped and 1781, and thought it was a planet-like comet. He actu- started going the other way. This should explain why ally wanted to call it Georgium Sidus as a tribute to it takes 243 days to fully rotate, but takes 225 days to the then King of England, King George III, but the get around the Sun. Venus is famed for having one of the thickest atmospheres of all the planets, and its name was predictably unpopular outside of Great Britain. Other proposed names were Neptune George proximity to the Sun might mean that gravity reacts III or Neptune Great Britain, which I actually don’t differently to it. This theory is known as Tidal Torque mind to be honest, being a Brit myself. A German sci- and might explain Venus’s retrograde rotation, espeentist, Johann Elert Bode then proposed Uranus, the cially if it got hit by another planet at some point. Latinized version of the Greek god of the sky, Ouranos. He said that the names of the planets should fol- The mystery isn’t solved but here is a fairly detailed low some order and he was probably right to be explanation of retrograde rotation honest.
Has dark energy had its day? by Rhodrii Evans
However, Adam Riess has co-authored an interesting guest blogpost in Scientific American, entitled “No, Astronomers Haven’t Decided Dark Energy Is Nonexistent”. Riess and his co-author Dan Scolnic (a cosmologist based at the University of Chicago’s Kavli Institute for Cosmological Physics) point out in this blogpost that the re-analysis by Nielsen etal. reduces the confidence that the Universe is accelerating to a 3-sigma result, which is still at a confidence level of 99.7%! So, it hardly does away with the need for acceleration, at a confidence of 99.7% it is still pretty likely. True, it now falls short of the usual 5-sigma result that scientists usually require for a “definite result”; but they also take issue with the way that Nielsen etal. have analysed their data. Also, as Scolnic and Riess point out, evidence for cosmic acceleration is not just based on the results from surveys of Type Ia supernovae. Studies of the details of the anisotropies in the cosmic microwave background also require dark energy (thought to be ���� ���� ���� a number of rumours of late responsible for cosmic acceleration), and so do surthat the evidence for dark energy is suspect, veys of the large scale structure of the Universe done and that maybe, after all, it doesn’t by surveys such as the Sloan Digital Sky Survey and exist. The stories are due to a paper which was the 2 Degree Field Galaxy Redshift Survey. recently published in Nature Scientific Reports. Unlike most papers published in Nature, which are This model, often called the concordance model, as it behind a paywall, this paper is available in its is supported by these 3 separate lines of evidence, is entirety for free. The authors argue that a larger data set of Type Ia supernovae, which were used in summarised in this figure. In this diagram, “BAO” are the 1990s as evidence for an accelerating Universe, the results from the large scale structure surveys (the now calls into question that whole interpretation of acronym stands for Baryonic Acoustic Oscillations). As the figure shows, the percentage of dark energy the data. required to explain the results of SN, CMB and BAO is about 70% (0.7 on the y-axis). This paper – “Marginal evidence for cosmic acceleration from Type Ia supernovae”, published in Nature Scientific Reports on 21 October 2016, This figure shows the so-called “concordance model”, calls into question the evidence for the existence of three separate lines of evidence which support the existence of dark energy at about the 70-80% level. The dark energy. figure is from Scolnic and Riess’s blogpost “No, AsThe 2011 Nobel prize for physics was awarded to tronomers Haven’t Decided Dark Energy Is NonexisSaul Perlmutter, Brian Schmidt and Adam Riess for tent”. their original “discovery” of cosmic acceleration, so if new data now call into question that whole idea it is, clearly, big news.
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You can read more about the three separate lines of evidence for dark matter in my book The Cosmic Microwave Background, How It Changed Our Understanding Of The Universe. My book “The Cosmic Microwave Background – how it changed our understanding of the Universe” is published by Springer. It seems to me that this is a lot of fuss about nothing, and that the case for cosmic acceleration is as strong as ever. What do you think?
The Largest Galaxy In The Observable Universe By Russell Adam Webb
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For someone growing up watching Captain Jean Luc Picard warping across the galaxy, it seems fairly simple. You have point A, you put dilithium crystals in the warp engine and you flash to point B. The only problem is that warp drive is just a theory and hasn’t yet been put into practice. Take Galaxy IC1101 for example. It was first observed, as many things in space were, by Frederick William Herschel I in his garden. It was then catalogued in 1895 by John Louis Emil Dreyer and came out as the 1,101st object of the Index Catalogue of Nebulae and Star Clusters, hence the name. Its size is truly astonishing. Firstly, its a long-ass way from here. It has been measured to reside approximately 320 megaparsecs away from us. That’s about a billion light years. So, even if we could travel at the speed of light, it would still take a billion years to get there. Furthermore, the light emanating from the galaxy takes a billion years to reach us and what we are seeing might not necessarily be what is there at this particular moment.