You might think you're just sitting there, reading my blog, maybe you're in a car, on a train or even on an airplane, also might be at home because of pandemic. But even if you were at home on your couch trying to be as still as possible, you're still traveling many miles per second. Sit still and think about that for a second… The question “how fast are we moving?” is far more difficult to answer than I thought because there are so many moving parts.
So, let's go through each level of motion and then add it all up at the end. Starting from small, you're not moving. Just to keep it simple, you're standing still on the equator. As the Earth rotates, the equator is going the fastest, and the poles are going slowest. If you were standing right on the north pole, you'd simply rotate once every day, but on the equator, you're going about 1,000 miles per hour (1600km) in a circle, every day.
You don't feel it, for the same reason you aren't stuck in your seat while a plane is flying, speed is relative, you only feel it when it changes. So anyway, you're already going 1,000 mph as a person. The Earth is traveling around the sun, once per year. It's a trip of 584 million miles (942 M km) to get the sun back to the exact same point in the sky. That means, the whole planet is flying at 66,667 mph (107k kph) as a planet!
Then, zooming out further, we are all tied to the movement of the sun. The sun is flying through the galaxy with all of us and planets tucked into its gravity. Scientists determined, the sun is moving toward other stars at around 45,000 miles per hour (72,420kph) but we're also moving "up" relative to our galactic disc at about 15,700 miles per hour (25.2k kph).
We're not going to fly out of the galaxy, the gravity of all those other stars is going to slow us down and pull us back in over the next 14 million years. And since we're about halfway out of the center of the Milky Way, and as far as we can tell the galaxy rotates once every 200 to 250 million years; we're moving approximately 550,000 miles per hour as a solar system. We're not done yet either!
You, the planet, the solar system and… The Milky Way. Our galaxy is heading toward the Andromeda galaxy at a pretty good clip. Numbers vary, a 2013 Space.com piece clocked it at 252,000 miles per hour. Again, with the three dimensional thinking, the Milky Way is also moving toward the constellation Hydra at about 1,342,000 mph (216M kph) and toward Virgo at like half that. So overall the Milky Way might be traveling as fast as 2,237,000 mph (3.6M kph).
The further away from you that you get, the more difficult it gets to measure your speed. The reason we use constellations and other galaxies is the same reason we use trees or mountains here on Earth to gauge distance. They're large and far enough away that they become a point of reference. We can measure our speed relative to theirs, but of course, all the stars and galaxies in Andromeda -- like a mountain -- are moving, Andromeda is moving, the stars of the constellation Hydra -- like the tree -- is moving… Everything is moving. And the whole universe might be moving.
Yep. I can get into that if you want! But some another day. It's big, y'all. Now, to the Maths!! Your 1,000 mph, plus Earth's 66,667 mph, plus our system's 550,000 mph, plus the galaxy's 2,237,000 miles per hour equals = about 2,855,000 miles per hour or about 800 miles every second.
Think about that. That's mind-boggling, and incredible. The reason you're not clinging to the ground in fright is because again, speed is relative. You're not feeling it because we're all on this supersonic jet together. Us, and all the stars in the galaxy. How does all this make you feel? Small? Tiny Insignificant? Or super amazing and important! And you still think you are sitting still?
