Why are planets round? Apparently we have gravity to thank…the force pushes the surface evenly inward (as seen from space at least). Gravity doesn’t help us draw circles however…these planets were just ‘first pass’ circles with no adjustment to the line. I like the thought that we’re all on one planet moving round, and turning round, getting up and going to sleep. Instead of ‘earth’ the picture reads ‘all of us’ though actually, it’s not quite true…visit this ‘one trick pony’ site to see how many of us are in space right now.