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well only the planets that are close to mars like mercury
Actually, the planets aren't all the same distance away.
The first factor is distance from the sun. Most of the planets are too close or too far from the sun making them too hot or too cold. All the planets other than Earth have unbreathable atmospheres or, in the case of Mercury, no atmosphere. The four outer planets are gas planets with no solid surfaces.
If all three planets are in a straight line, then Earth and Venus are closer (~42 milion km) than Mercury and Venus (~50 million km) but since all three planets have different orbital periods, it is possible for Earth to be on the opposite side of the Sun from Venus and Mercury, in which case they would be closer to each other than Earth was to either of them.
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Because it has less distance to travel around the Sun.
The other two planets are Mercury and Venus.
stuff
mercury is very very heater than other planets
Earth, Venus, and Mercury are also inner planets.
Mercury, Venus, Earth, and Mars are called the inner planets.
Mercury and Venus have no known satellites, all other planets have at least one.
well only the planets that are close to mars like mercury
They are classified as terrestrial planets. The other grouping is called the gas giant planets.
Mercury has no twin planet, it is not really like any of the other planets.
Actually, the planets aren't all the same distance away.