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Orbital Physics Is Child’s Play With ‘Super Planet Crash’


This screenshot from the online game Super Planet Crash shows a six-planet system.

This screenshot from the online game Super Planet Crash shows a six-planet system.

A new game and online educational resources are offshoots of the open-source software package astronomers use to find planets beyond our solar system.

Super Planet Crash is a pretty simple game: players build their own planetary system, putting planets into orbit around a star and racking up points until they add a planet that destabilizes the whole system. Beneath the surface, however, this addictive little game is driven by highly sophisticated software code that astronomers use to find planets beyond our solar system (called exoplanets).

The release of Super Planet Crash (available online at http://www.stefanom.org/spc) follows the release of the latest version of Systemic Console, a scientific software package used to pull planet discoveries out of the reams of data acquired by telescopes such as the Automated Planet Finder (APF) at the University of California’s Lick Observatory. Developed at UC Santa Cruz, Systemic Console is integrated into the workflow of the APF, and is also widely used by astronomers to analyze data from other telescopes.

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Mystery Of Planet-forming Disks Explained By Magnetism


Artist's conception. Image credit: NASA/JPL-Caltech

Artist’s conception. Image credit: NASA/JPL-Caltech

Astronomers say that magnetic storms in the gas orbiting young stars may explain a mystery that has persisted since before 2006.

Researchers using NASA’s Spitzer Space Telescope to study developing stars have had a hard time figuring out why the stars give off more infrared light than expected. The planet-forming disks that circle the young stars are heated by starlight and glow with infrared light, but Spitzer detected additional infrared light coming from an unknown source.

A new theory, based on three-dimensional models of planet-forming disks, suggests the answer: Gas and dust suspended above the disks on gigantic magnetic loops like those seen on the sun absorb the starlight and glow with infrared light.

“If you could somehow stand on one of these planet-forming disks and look at the star in the center through the disk atmosphere, you would see what looks like a sunset,” said Neal Turner of NASA’s Jet Propulsion Laboratory, Pasadena, Calif.

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Bullying Black Holes Force Galaxies To Stay Red And Dead

February 26, 2014 Leave a comment

Copyright: Digitised Sky Survey/NASA Chandra/Southern Observatory for Astrophysical Research/Very Large Array (Robert Dunn et al. 2010)

Copyright: Digitised Sky Survey/NASA Chandra/Southern Observatory for Astrophysical Research/Very Large Array (Robert Dunn et al. 2010)

Giant elliptical galaxies are the most puzzling type of galaxy in the Universe. Since they mysteriously shut down their star-forming activity and remain home only to the longest-lived of their stars – which are low-mass ones and appear red – astronomers often call these galaxies ‘red and dead’.

Up until now, it was thought that red-and-dead galaxies were poor in cold gas – the vital raw material from which stars are born. While cold gas is abundant in spiral galaxies with lively star formation, the lack of it in giant ellipticals seemed to explain the absence of new stars.

Astronomers have long been debating the physical processes leading to the end of their star formation. They speculated that these galaxies somehow expelled the cold gas, or that they had simply used it all to form stars in the past. Although the reason was uncertain, one thing seemed to have been established: these galaxies are red and dead because they no longer possess the means to sustain the production of stars.

This view is being challenged by a new study based on data from ESA’s Herschel Space Observatory. The results are published in Monthly Notices of the Royal Astronomical Society.

“We looked at eight giant elliptical galaxies that nobody had looked at with Herschel before and we were delighted to find that, contrary to previous belief, six out of eight abound with cold gas”, explains Norbert Werner from Stanford University in California, USA, who led the study.
This is the first time that astronomers have seen large amounts of cold gas in red-and-dead galaxies that are not located at the centre of a massive galaxy cluster.

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Commentary On The Press Release “A Drastic Chemical Change Occurring In Birth Of Planetary System: Has The Solar System Also Experienced it?”

February 13, 2014 Leave a comment

An infrared image of the protostar L1527 taken by the Spitzer Space Telescope. Credit: J. Tobin/NASA/JPL-Caltech

An infrared image of the protostar L1527 taken by the Spitzer Space Telescope.
Credit: J. Tobin/NASA/JPL-Caltech

Stars are formed by the contraction of interstellar gas and dust. Around a protostar, gas and dust form a disk in which planets are eventually formed. Then, are the chemical compositions of the interstellar cloud and the disk identical? The new ALMA observations show that the answer is ‘no.’ This finding has a large impact on understandings of the formation process of planets and protoplanetary disks.

The international research team, led by Dr. Nami Sakai, an assistant professor at the Department of Physics, The University of Tokyo, observed a baby star L1527 in the constellation Taurus with ALMA. The team observed radio emission from cyclic-C3H2 [note 1] and sulfur monoxide (SO) molecules to analyze the motion and temperature of the gas around the baby star.

L1527 is a well-known protostar (baby star) and many astronomers have pointed telescopes at it. For example, NASA’s Spitzer Space Telescope took infrared images of the star. The stellar light escapes through a cavity excavated by a powerful bipolar gas flow from the star and illuminates the surrounding gas, which makes a butterfly-shaped nebula extending in the east-west direction (Figure 1). Past radio observations revealed that gas is circling around the star to form a disk and we see the disk edge-on.

Radio observations by ALMA have the advantage of being able to see the gas directly, which is invisible in infrared light. Various molecules in the gas emit characteristic radiation as radio waves under characteristic conditions (temperature, density, chemical compositions). Therefore astronomers can investigate the nature of the gas by observing various molecules.

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ALMA Discovers A Formation Site Of A Giant Planetary System

January 21, 2014 Leave a comment

Credit: ALMA (ESO/NAOJ/NRAO), Fukagawa et al.

Credit: ALMA (ESO/NAOJ/NRAO), Fukagawa et al.

A team of Japanese astronomers has obtained a firm evidence of formation of a giant planetary system around a young star by the observations with the Atacama Large Millimeter/submillimeter Array (ALMA). This result has a transformative impact on the theories of planet formation and gives us a clue to the origin of a wide variety of planetary systems.

The research team, led by astronomers at Osaka University and Ibaraki University, observed a young star named HD142527 in the constellation Lupus (the Wolf) with ALMA. The ALMA image shows that cosmic dust, which is component material of planets, is circling around the star in a form of asymmetric ring. By measuring the density of dust in the densest part of the ring, the astronomers found that it is highly possible that planets are now being formed in that region. This region is far from the central star, about 5 times larger than the distance between the Sun and the Neptune. This is the first firm evidence of planet formation found so far from the central star in a protoplanetary disk. The research team plans further observations of HD142527 with ALMA for closer investigation, as well as other protoplanetary disks to have a comprehensive understanding of the planet formation in general.

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Starless Cloud Cores Reveal Why Some Stars Are Bigger Than Others

December 20, 2013 Leave a comment

Credit: Bill Saxton & Alexandra Angelich (NRAO/AUI/NSF); ALMA (ESO/NAOJ/NRAO)

Credit: Bill Saxton & Alexandra Angelich (NRAO/AUI/NSF); ALMA (ESO/NAOJ/NRAO)

Massive stars – those at least 8 times the mass of our Sun – present an intriguing mystery: how do they grow so large when the vast majority of stars in the Milky Way are considerably smaller?

To find the answer, astronomers used the Atacama Large Millimeter/submillimeter Array (ALMA) telescope to survey the cores of some of the darkest, coldest, and densest clouds in our Galaxy to search for the telltale signs of star formation.

To find the answer, astronomers used the Atacama Large Millimeter/submillimeter Array (ALMA) telescope to survey the cores of some of the darkest, coldest, and densest clouds in our Galaxy to search for the telltale signs of star formation.

Since these cloud cores are so massive and dense, gravity should have already overwhelmed their supporting gas pressure, allowing them to collapse to form new, Sun-mass stars. If a star had not yet begun to shine, that would be a hint that something extra was supporting the cloud.

“A starless core would indicate that some force was balancing out the pull of gravity, regulating star formation, and allowing vast amounts of material to accumulate in a scaled-up version of the way our own Sun formed,” remarked Jonathan Tan, an astrophysicist at the University of Florida, Gainesville, and lead author of a paper published today in the Astrophysical Journal. “This suggests that massive stars and Sun-like stars follow a universal mechanism for star formation. The only difference is the size of their parent clouds.”

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Hidden Details Revealed In Nearby Starburst Galaxy: Green Bank Telescope’s New Vision Debuts

December 9, 2013 Leave a comment

Composite image of starburst galaxy M82. CREDIT: Bill Saxton (NRAO/AUI/NSF); Hubble/NASA

Composite image of starburst galaxy M82. CREDIT: Bill Saxton (NRAO/AUI/NSF); Hubble/NASA

Using the new, high-frequency capabilities of the National Science Foundation’s Robert C. Byrd Green Bank Telescope (GBT), astronomers have captured never-before-seen details of the nearby starburst galaxy M82. These new data highlight streamers of material fleeing the disk of the galaxy as well as concentrations of dense molecular gas surrounding pockets of intense star formation.

M82, which is located approximately 12 million light-years away in the constellation Ursa Major, is a classic example of a starburst galaxy — one that is producing new stars tens- to hundreds-of-times faster than our own Milky Way. Its relatively nearby location made it an ideal target for the GBT’s newly equipped “W-Band” receiver, which is capable of detecting the millimeter wavelength light that is emitted by molecular gas. This new capability makes the GBT the world’s largest single-dish, millimeter-wave telescope.

“With this new vision, we were able to look at M82 to explore how the distribution of molecular gas in the galaxy corresponded to areas of intense star formation,” said Amanda Kepley, a post-doctoral fellow at the National Radio Astronomy Observatory (NRAO) in Green Bank, West Virginia, and lead author on a paper accepted for publication in the Astrophysical Journal Letters. “Having this new capability may help us understand why stars form where they do.”

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