Answer:
The planets of the solar system are 8:
Mercury is the planet closest to the sun, and therefore the hottest planet in stable conditions. It has an average temperature of 160º C, but with nights of up to -170º C. It is a rocky planet, and it does not have satellites. Its period of rotation around the sun is 88 days.
Venus is also a rocky planet, but considerably larger than Mercury. It has an average temperature of 460º C, due to its enormous atmospheric pressure, thus surpassing Mercury, which is even closer to the sun. Its rotation period is 225 days, and it does not have satellites either.
The Earth, our planet, is the only one with ideal conditions for the development of life: it has a rotation of 365 days, an average temperature of 15ºC and water in sufficient abundance to allow the development of oxygen-producing vegetation.
Mars, the last rocky planet in the chain, has a rotation period of 687 days, an average temperature of -46º C and minimal amounts of water. It has 2 satellites.
Then we have the gaseous planets, which are Jupiter, Saturn, Uranus, and Neptune. These do not have a solid surface, but are composed of gases (and portions of ice due to the extremely high temperature they have, from -120ºC to -220ºC) and enormous amounts of satellites. These are the least fit for life, due to their temperature and lack of solidity.
