COSMIC YEAR

The time it takes us to orbit the center of the galaxy – is known as a cosmic year.

The Milky Way galaxy is huge - about 100,000 light years across. Recent estimates put the distance from the sun to the Galactic center at 26,100 light-years, and that the Galactic rotation velocity in the solar system is 240km/s. (The entire galaxy is rotating, like a pinwheel). This means, the Sun along with it's entourage of planets, their moons, and everything else in the solar system is orbiting the center of the galaxy at 864,000 km per hour. Even at this terrific speed, the sun takes approximately 225 million years to complete one journey around the galaxy’s center. This is known as the cosmic year.

So far, the Sun has completed 20 orbits since its formation. That's 20 Cosmic Years, I guess.