Jupiter-like planets have masses between 0.5 and 13 Jupiter masses.
The main components are hydrogen and helium.
It is highly likely that there is a core composed of rock, metal, and ice inside.
As it goes inside, it seems to go from gas to liquid to metallic hydrogen.
It rotates at a high speed and is likely to have satellites. The gas giants of our solar system would be one of them. People investigating the Kepler spacecraft images say it's likely that the satellite's transit light is visible in the Kepler data. Furthermore, Jupiter's Io and moons like Ganymede can be caught in transit. Kepler has discovered exoplanets smaller than the moon.
Criterion of Jupiter-like planets
Moderator: Franck