Latest Circumstellar discs Stories

2005-07-21 07:42:14

Gemini -- A relatively young star located about 300 light-years away is greatly improving our understanding of the formation of Earth-like planets. The star, going by the unassuming name of BD +20 307, is shrouded by the dustiest environment ever seen so close to a Sun-like star well after its formation. The warm dust is believed to be from recent collisions of rocky bodies at distances from the star comparable to that of the Earth from the Sun. The results were based on observations...

2005-07-19 12:45:00

Cambridge, MA -- Every rule has an exception. One rule in astronomy, supported by considerable evidence, states that dust disks around newborn stars disappear in a few million years. Most likely, they vanish because the material has collected into full-sized planets. Astronomers have discovered the first exception to this rule - a 25-million-year-old dust disk that shows no evidence of planet formation. "Finding this disk is as unexpected as locating a 200-year-old person," said astronomer...

2005-06-24 10:24:01

Cambridge, MA -- Interstellar travelers might want to detour around the star system TW Hydrae to avoid a messy planetary construction site. Astronomer David Wilner of the Harvard-Smithsonian Center for Astrophysics (CfA) and his colleagues have discovered that the gaseous protoplanetary disk surrounding TW Hydrae holds vast swaths of pebbles extending outward for at least 1 billion miles. These rocky chunks should continue to grow in size as they collide and stick together until they...

2005-06-21 22:40:00

Berkeley - Astronomers zooming in on a nearby star with NASA's Hubble Space Telescope have discovered unmistakable evidence of a planetary system: a perturbed dusty belt around the star that's analogous to the vast Kuiper Belt of icy rocks encircling the sun. While the discovery is expected to send astronomers scurrying to their telescopes to obtain direct images of a planet around the star, called Fomalhaut, it also provides a Rosetta stone for debris disks - the pancakes of rock and ice...

2005-06-22 12:15:00

NASA -- The Hubble Space Telescope's most detailed visible-light image ever taken of a narrow, dusty ring around the nearby star Fomalhaut (HD 216956), offers the strongest evidence yet that an unruly and unseen planet may be gravitationally tugging on the ring. Hubble unequivocally shows that the center of the ring is a whopping 1.4 billion miles (15 astronomical units) away from the star. This is a distance equal to nearly halfway across our solar system. The most plausible explanation,...

2005-06-15 09:24:37

Cambridge, MA -- Astronomers find jets everywhere when they look into space. Small jets spout from newborn stars, while huge jets blast out of the centers of galaxies. Yet despite their commonness, the processes that drive them remain shrouded in mystery. Even relatively nearby stellar jets hide their origins behind almost impenetrable clouds of dust. All stars, including our sun, pass through a jet phase during their "childhood," so astronomers are eager to understand how jets form and how...

2005-05-26 00:50:00

Astrobiology Magazine -- People of every culture have been fascinated by the dark "spots" on the Moon, which seem to compose the figure of a rabbit, frogs or the face of a clown. With the Apollo missions, scientists found that these features are actually huge impact basins that were flooded with now-solidified lava. One surprise was that these basins formed relatively late in the history of the early solar system -- approximately 700 million years after the formation of the Earth and...

2005-05-24 07:25:00

The most detailed measurements to date of the dusty disks around young stars confirm a new theory that the region where rocky planets such as Earth form is much farther away from the star than originally thought. These first definitive measurements of planet-forming zones offer important clues to the initial conditions that give birth to planets. Astrobiology Magazine -- The most detailed measurements to date of the dusty disks around young stars confirm a new theory that the region where...

2005-05-10 12:20:00

Young stars in the Orion Nebula have quite a temper, flashing powerful X-rays every few days. Scientists wonder if such X-ray flares could rough up the calm sea of a proto-planetary disk, and thereby rescue burgeoning planets from certain oblivion. Does a temperamental youth ensure the existence of future planets? NASA -- Orion the Hunter is one of the most easily recognized constellations in the night sky, and lying just beneath his belt is the Orion Nebula, a nursery that cradles about...

2005-04-21 07:38:17

NAOJ -- Detailed new images of the starbirth nursery in the Omega Nebula (M17) have revealed a multi component structure in the envelope of dust and gas surrounding a very young star. The stellar newborn, called M17-SO1, has a flaring torus of gas and dust, and thin conical shells of material above and below the torus. Shigeyuki Sako from University of Tokyo and a team of astronomers from the National Astronomical Observatory of Japan, the Japan Aeorospace Exploration Agency, Ibaraki...

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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Word of the Day
  • The call or cry of a bird or other animal to its mate or its young.
'Call-note' is newer than 'bird-call,' which originally referred to 'an instrument for imitating the note of birds' but now also refers to 'the song or cry of a bird.'