Why is the Earth round?
July 27, 2008Firstly, Earth is not round. Not perfectly round, that is. This is becasue of the effect of gravity, which is a central force. Gravity pulls things together along a traight line. The bigger a body is, the stronger it is pulled toward this central force. When the earth was forming, it was mainly just the remains of an exploded sun (a supernova). Most of the remaining matter condensed into a big fiery ball, which is now what we know as our sun. Some of the dust particles that remained were far enough from the sun that the stronger forces were between planetary dust particles, and not the sun. Thus, the focus of gravitational pull was different. These dust particles swirled together into a ball, which we now identify as planets. This explains why planets, Earth being one of them, are spherical in shape.

