Gas giants are large planets mostly composed of helium and/or hydrogen. Although these planets have dense cores, they don't ...

The planets in our solar system grew out of a disk of material that swirled around our Sun. Inner rocky planets formed as tiny grains stuck together ...

Astronomers have found evidence of a process that supports an alternative, more rapid approach to planetary formation, more top down than bottom up. By Katrina Miller When it comes to making a planet, ...

One way gas giants form is through core accretion, where solid cores gradually grow in a disk by pulling in rocky and icy pebbles until they become massive enough to attract the gas that surrounds ...

The discovery provides new insights into the question, 'how large can a planet be?' An illustration of the HR 8799 system with three of its gas ...

Astronomers have discovered an extrasolar planet with the largest core of any known planet. The discovery is especially exciting to planet formation theorists, because it provides extremely strong ...

Rocky planets such as Earth and Mars are born when small particles smash together to form larger, planet-sized clusters in a planet-forming disk, but researchers are less sure about how gas-giant ...

The Saturn System has been studied in detail by the Cassini-Huygens Mission. A major thrust of those investigations has been to understand how Saturn formed and evolved and to place Saturn in the ...