There are 464 extrasolar planets, and 8 planets within our Solar System. This makes a total of 470 known planets.
Mercury. It has the longest cycle of ALL the planets, not just terrestrial.
outer planets.
''Mercury (shortest),''Neptune (longest)
Yes because they are rocky planets and the outer planets are known as the gas planets.
All of a persons life
Neptune takes the longest
Mars takes the longest of the inner planets.
The inner planets are known as terrestrial planets because they are rocky like earth
Neptune
Neptune
mercury and venus are known as light planets, because they are closest to the sun.