Like the other hundred billion stars in the Milky Way disk, the Sun circles around the galaxy at a speed of about 220 kilometers per second. At this speed, it takes about 240 million years for the Sun to orbit the galactic center. Since the galactic plane is less than 10 billion years old, the stars in the plane have made less than 50 revolutions in that time. It’s enough time for the system to homogenize some gross features, but really it’s not all that many trips around.
