Latest Circumstellar discs Stories

2006-02-21 07:37:41

AAAS -- In the search for life on other worlds, scientists can listen for radio transmissions from stellar neighborhoods where intelligent civilizations might lurk or they can try to actually spot planets like our own in habitable zones around nearby stars. Either approach is tricky and relies on choosing the right targets for scrutiny out of the many thousands of nearby stars in our galactic neighborhood. Margaret Turnbull, an astronomer at the Carnegie Institution of Washington, has...

2006-01-19 11:57:41

NASA -- These two bright debris disks of ice and dust appear to be the equivalent of our own solar system's Kuiper Belt, a ring of icy rocks outside the orbit of Neptune and the source of short-period comets. The disks encircle the types of stars around which there could be habitable zones and planets for life to develop. The disks seem to have a central area cleared of debris, perhaps by planets. The new disks, each about 60 light-years from Earth, bring to nine the number of dusty debris...

2006-01-12 06:15:00

Washington DC -- New theoretical work shows that gas-giant planet formation can occur around binary stars in much the same way that it occurs around single stars like the Sun. The work is presented today by Dr. Alan Boss of the Carnegie Institution's Department of Terrestrial Magnetism (DTM) at the American Astronomical Society meeting in Washington, DC. The results suggest that gas-giant planets, like Jupiter, and habitable Earth-like planets could be more prevalent than previously thought....

2006-01-10 06:25:00

WASHINGTON, D. C. -- New observations of the Orion Nebula at infrared wavelengths reveal that small dust grains located in disks around young stars are growing, taking the initial steps toward forming planets despite bathing in a flood of radiation from highly luminous stars. The properties of dust in disks around young stars plays a pivotal role in understanding star formation and determining the origins of planets in our Solar system and in extrasolar planetary systems as well. The results...

2005-12-17 18:25:00

NASA -- Astronomers have found a debris disk around a sun-like star that may be forming or has formed its terrestrial planets. The disk - a probable analog to our asteroid belt - may have begun a solar-system-scale demolition derby, where the rocky remains of failed planets collide chaotically. "This is one of a very rare class of objects that may give us a glimpse into what our solar system may have looked like during the formation of our terrestrial planets," said Dean C. Hines of the...

2005-11-29 15:45:00

Cambridge, MA -- Astronomers using NASA's Spitzer Space Telescope have discovered a remarkably small brown dwarf surrounded by a dusty disk. The brown dwarf contains only about 8 times the mass of Jupiter, making it one of the smallest known brown dwarfs. It is even smaller than several planets around other stars, leading to the question of whether any objects that form from the disk around it should be considered planets or moons. "There are two camps when it comes to defining planets...

2005-10-25 19:30:00

Thus, the process of building planets is more universal and robust than had previously been assumed (Science Express, October 20, 2005). Brown dwarfs, like more massive normal stars, are formed when interstellar gas and dust clouds collapse. When this happens, a central, dense area builds up, embedded in a rotating disc made of gas and dust. These circumstellar discs produce infrared radiation according to their temperature. The collapse of gas and dust clouds ends when the increasing...

2005-09-20 16:17:01

Cambridge, MA -- Newborn stars are difficult to photograph. They tend to hide in the nebulous stellar nurseries where they formed, enshrouded by thick layers of dust. Now, Smithsonian astronomer T.K. Sridharan (Harvard-Smithsonian Center for Astrophysics) and his colleagues have photographed a pair of stellar twins in infrared light, which penetrates the dust. And these babies are whoppers, weighing several times the mass of the Sun. Moreover, Sridharan's images reveal a circumstellar disk...

2005-09-12 15:25:00

JPL -- According to the most popular theory of planet formation, planets are akin to redwood trees, growing in size very gradually. Rocky planets like Earth develop over millions of years, followed by gas giants like Jupiter, which build upon rocky cores. But new evidence from NASA's Spitzer Space Telescope suggests that some gas giants may sprout in less than one million years, more like planetary wildflowers than trees. The evidence comes in the form of gaps and holes. Planets are born...

2005-09-09 18:43:10

Using NASA's Spitzer Space Telescope, a team of astronomers led by the University of Rochester has detected gaps ringing the dusty disks around two very young stars, which suggests that gas-giant planets have formed there. A year ago, these same researchers found evidence of the first "baby planet" around a young star, challenging most astrophysicists's models of giant-planet formation. The new findings in the Sept. 10 issue of Astrophysical Journal Letters not only reinforce the idea that...

Latest Circumstellar discs Reference Libraries

2004-10-19 04:45:44

Cosmogony -- Cosmogony is the study of the origins of celestial objects. It is most commonly used to refer to the study of the origin of the solar system. Currently, the most widely accepted theory is that the solar system was formed roughly 5 billion years ago with the collapse of a nebula of gas and dust, likely caused by shock waves generated by a nearby supernova. The solar system would have formed as a member of a star cluster, now long-since dispersed throughout the Milky Way over...

2004-10-19 04:45:41

Asteroid Belt -- The Asteroid belt is a region of the solar system falling roughly between the planets Mars and Jupiter where the greatest concentration of asteroid orbits can be found. It is believed that, during the first million years of the solar system history, planets formed by accretion of planetesimals. Ripetute collisions led to the familiar rocky planets and to the gas giant's cores. However, in this zone of the system the strong gravity of Jupiter inhibited the final stages...

2004-10-19 04:45:40

Vega -- Vega (Alpha Lyrae) is the lead star in the constellation Lyra, reaching near directly overhead the mid-northern latitudes, during the summer. It's a "nearby star" at only 25 light years distant and together with Arcturus and Sirius, one of the brightest stars in the Sun's neighbourhood. Vega is a vertex of the Summer Triangle. Its spectral class is A0V (Sirius, an A1V, is slightly less powerful) and it's firmly in the main sequence, fusing hydrogen to helium in its core....

2004-10-19 04:45:40

Epsilon Eridani -- Epsilon Eridani is a main-sequence star in the constellation of Eridanus (the river). It is often used in science fiction because it is extremely sunlike, and in the fictional Star Trek universe it is the home sun of the planet Vulcan which is home to Mr. Spock. It is the third closest star visible without a telescope. It has 85% of the Sun's mass, almost that much of its diameter, and 28% of its luminosity. It is 10.5 light years from Earth. Its spectrum is...

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