Posts tagged trillion

September 27, 2003

Hold on a Parsec

One parsec is three point two six light years. And contrary to popular belief, a light year isn’t a unit of time at all! It’s also a unit of distance.

How fast anything spins is partly determined by how its weight is distributed. The closer an object’s weight is to its axis of rotation, the faster it spins. To picture this, imagine an ice skater doing a pirouette. When her arms are extended, she spins slowly.