. Galileo Galilei was the first astronomer to use a telescope to study the heavens. Galileo made a number of observations that finally helped convince people that the Sun-centered solar system model (the heliocentric model), as proposed by Copernicus, was correct.
As the moisture-rich air approaches the mountain, it rises and cools, and water molecules in the air combine to form small drops. The process where water vapor becomes a liquid is called condensation.