“Fun Facts Saturday”
I am fascinated by cosmology and issues of space–time. (That’s why I like science fiction and “Space Opera.”) Unfortunately, my college didn’t offer “Cosmology for Dummies” for us English majors.
I long wondered: “How fast are we travelling through space?”
The answer: about 1.78 million miles per hour!
Speed of Earth’s Rotation (1,000 mph)
The earth is roughly 25,000 miles in circumference around the equator. The earth rotates in about 24 hours (1 day). So, we are rotating around 1,000 miles per hour. (25,000 ÷ 24 = 1041)
Speed of Earth’s Orbit Around the Sun (67,000 mph)
The earth is 93 million miles from the sun. The circumference of the earth’s orbit around the sun is about 584 million miles. It takes the earth roughly 365 days (1 year) to travel that distance. So, we are orbiting the sun at a speed of about 67,000 miles per hour. (584,000,000 ÷ 365 ÷ 24 = 66,666)
Speed of Sun’s Orbit Around the Milky Way Galaxy (483,000 mph)
It takes our sun roughly 225-250 million years (1 “Galactic Year”) to orbit the center of the Milky Way Galaxy. Our orbiting speed is about 483,000 miles per hour.
Speed of Milky Way Galaxy Moving Through Space (1,300,000 mph)
The Milky Way Galaxy is traveling through the universe at 1.3 million miles per hour. I don’t know how they calculate that speed, but I will take their word for it.
So, how fast are we moving? Total: 1,783,000 miles per hour
1,000 mph (Earth’s rotation)
+ 67,000 mph (Earth’s orbit around sun)
+ 483,000 mph (Sun’s orbit around galaxy)
+ 1,300,000 mph (Galaxy through space)
Total = 1,783,000 mph
No wonder I feel so tired all the time!
Why don’t we feel the velocity?
Basically, we don’t sense velocity that is constant. We only perceive change of speed, like acceleration and deceleration. For example, we don’t feel like we’re flying 500 mph in a commercial jet, but we do feel the rapid change when the plane accelerates during take off or decelerates during landing.
Now, you know.
(See: “Galactic Year,” Wikipedia)