The center of the Milky Way galaxy with the supermassive black hole located in the middle (26,000 light years from Earth). Image combines X-rays from Chandra X-Ray Observatory Telescope with infrared emission from the Hubble Space Telescope.
See Which Way The Earth, Sun, and Milky Way Are Moving
Of course, we all know that planet Earth orbits around the Sun.
But the Sun is not stationary. The Sun and its solar system (including Earth) reside in an arm of the Milky Way galaxy. The Sun orbits the center of our huge Milky Way galaxy in an elliptical shape.
Further, our Milky Way galaxy is not stationary either! It’s also revolving. We’ll get to this in a moment …
Now get ready for something deep. This isn’t frivolous stuff!
First, Find Saturn—And the Center of our Galaxy (A Black Hole)
Okay, it’s 9 p.m. and your task is to look around and find the brightest star in the whole sky. Facing south, you’ll find that it is low in the sky and distinctly orange. This is Mars and you’ll see that it’s not horizon-scraping low, but floats only about 1/4 of the way up the southern sky. Now you’ll use Mars to find two important landmarks, or maybe we should say “skymarks.”
Keep looking to the right of Mars until you come to the first bright-ish star. This is the planet Saturn, and if you own a backyard telescope, this is the finest target in the summer sky. But right now we’re not stopping at Saturn.
Instead, we’re learning an amazing thing: If you looked way, way beyond Saturn, you’ll find the center of the Milky Way. Yep, Saturn happens to be sitting in front of the center of our galaxy. That part of the sky where Saturn is, but lying 25,000 light years in the far distance, is the supermassive black hole around which our entire galaxy revolves.
That’s right, every star you can ever see revolves around that spot. Including our own Sun.
Now Find Vega—And The Direction We’re Headed
Okay, but if we’re circling that spot every quarter billion years, it’s reasonable to wonder which direction we’re going. The answer is easy these nights.
Go back to Mars and look high, high above it. And there, very nearly straight up, is a brilliant bluish star—the famous Vega.
Just to the left of Vega, well, that’s the direction Earth and Sun are zooming at 144 miles per second as we circle the center of our galaxy.
Wow. Everyone knows that our world circles around the Sun once a year. But that’s a relatively slow odyssey at just 18 miles per second. While we’re doing that, the Sun, taking us along for the ride, is zooming 144 miles per second in this direction to the left of Vega as we circle around the galactic core which is just below (and far behind) Saturn.
So, now you’ve found Saturn and the center of our Milky Way galaxy. And you’ve found Vega and the direction that the Earth and our entire solar system is heading.
What did that take? Two minutes? And then all of a sudden you’re the only one of your friends who knows where we’re all going.