Astonishing Length Of A Galactic Year | Sun’s Orbit Around Milky Way: The moon orbits the Earth, the Earth orbits the sun, and the sun orbits the Milky Way and in 1999, Astronomers focused on a star at the center of the Milky Way and measured precisely for the first time how long it takes the sun to complete one orbit (a galactic year) of our home galaxy. The answer 226 million years. That means that when the last galactic orbit was completed, dinosaurs ruled the world. The Solar System is thought to have completed about 20–25 orbits during its lifetime or 0.0008 orbit since the origin of humans since it was formed around 4.5 billion years ago.
Using the Hubble Space Telescope, the astronomers focused on Sagittarius A, a star discovered over two decades ago to mark the Milky Way’s center and plotted the motion of the Milky Way and found that the sun and its family of planets were orbiting the galaxy at about 135 miles per second which means the sun circles the Milky Way at a speed of about 486,000 miles per hour. And keep in mind that every object in the universe is moving apart from the other objects as the universe expands at a constantly accelerating rate. Thea astronomer’s measurement supports the idea that the Milky Way’s center contains a supermassive black hole which is about 2.6 million times more massive than the sun.
The sun is one of about 100 billion stars in the Milky Way, one of billions of ordinary galaxies in the universe. The Milky Way is a spiral galaxy, with curving arms of stars pinwheeling out from a center.The solar system is about halfway out on one of these arms and is about 26,000 light years from the center. A light year is about 6 trillion miles