Models of
planetary formation suggest that giant extrasolar planets detected very near their stars formed at greater distances and migrated inward as a result of gravitational interactions with remnants of the circumstellar disks from which they accumulated.
Not exact matches
The new study
suggests that the «hot Jupiter» WASP - 18b, a massive planet that orbits very close to its host star, has an unusual composition, and the
formation of this world might have been quite different from that of Jupiter as well as gas giants in other
planetary systems.
The simulations
suggest that
planetary bodies the size of the moon existed prior to the creation of the earliest chondrules, and that it was the enormous pressures produced by a collision between two such bodies that were responsible for the
formation of the glassy spheres.
As the zircons were radioactively dated to be as old as 4.25 billion years, the new findings
suggest that carbon - based life may have been present on Earth within the first 300 million years after
planetary formation, possibly as a «
planetary mega-organism» in Earth's oceans (Michael Marshall, New Scientist, November 25, 2011).
None of the approximately 750,000 known asteroids and comets in the Solar System is thought to have originated outside it, despite models of the
formation of
planetary systems
suggesting that orbital migration of giant planets ejects a large fraction of the original planetesimals into interstellar space1.