The planet closest to the Sun is Mercury, then Venus, and next is Earth.
An Earthling’s loudest cheer should be, “We’re number three!” Everything about Earth is just right for the presence of life as we know it. It is at just the right distance from the Sun for water to remain liquid, rather than evaporate or freeze, and all life as we know it depends on water.
We’re not the smallest! That’s the next loudest cheer for Earthlings. Smaller planets have a weak gravitational pull, so puny that they can’t retain an atmosphere and gases just escape out into space. Earth’s gravity is strong enough to retain the thin layer of gases that make up its atmosphere, which is the air we breathe. Earth’s atmosphere protects us from deadly solar rays and keeps the planet from becoming frozen solid.
We’re just right! If Earth were even a tiny bit “wrong,” life could not exist.
