Latest Circumstellar discs Stories
By using a computer program to play a complex game of "what if," scientists have developed a tale of chaos in the early solar system that they say explains several mysteries about why our cosmic neighborhood turned out the way it did.
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.
New results from NASA's Chandra X-ray Observatory imply that X-ray super-flares torched the young Solar System. Such flares likely affected the planet-forming disk around the early Sun, and may have enhanced the survival chances of Earth.
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.
NASA's Spitzer Space Telescope has spotted what may be the dusty spray of asteroids banging together in a belt that orbits a star like our Sun. The discovery offers astronomers a rare glimpse at a distant star system that resembles our home, and may represent a significant step toward learning if and where other Earths form.
A new theory of how planets form finds havens of stability amid violent turbulence in the swirling gas that surrounds a young star. These protected areas are where planets can begin to form without being destroyed. The theory will be published in the February issue of the journal Icarus.
Astronomers say a dusty disc swirling around the nearby star Vega is bigger than earlier thought. It was probably caused by collisions of objects, perhaps as big as the planet Pluto, up to 2,000 kilometers (about 1,200 miles) in diameter.
Spitzer has discovered for the first time dusty discs around mature, Sun-like stars known to have planets. Hubble captured the most detailed image ever of a brighter disc circling a much younger Sun- like star. The findings offer "snapshots" of the process by which our own solar system evolved, from its dusty and chaotic beginnings to its more settled present-day state.
One of the currently hottest astrophysical topics - the hunt for Earth-like planets around other stars - has just received an important impetus from new spectral observations with the MIDI instrument at the ESO VLT Interferometer (VLTI).
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...
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...
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....
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...
- Having no light.
- Of or relating to the region of a body of water that is not reached by sunlight and in which photosynthesis is unable to occur.