The Earth is constantly moving, and as it revolves around the sun, it also rotates on its axis, like a basketball on the tip of a player’s finger.
The Earth rotates on its axis once every 24 hours, or, to be precise, every 23 hours 56 minutes and 4 seconds. The circumference of the planet is 24,898 miles (40.070 km), so when you divide the distance by time, it means that the planet is spinning 1,037 miles per hour (1,670 km/h).
Meanwhile, the Earth is orbiting the sun at about 67,000 miles per hour (110,000 km/h), according to Ask an Astronomer, a blog run by astronomers at Cornell University in Ithaca, New York.
It takes the Earth about 365 days to complete one orbit around the sun, in an elliptical orbit.
To calculate the distance of the Earth around the sun, all scientists need is to determine the circumference of the circle. We know that the Earth is, on average, about 93 million miles (149.6 million km) from the Sun, and we know that it moves in a generally circular path (it’s actually more elliptical, but it’s easier to do this equation using a circle). And that distance between the Sun and the Earth is the radius of the circle.
To get the circumference of that circle, the equation is 2×π× radius, or 2×3.14×93 million miles.
Once the circumference (the distance the Earth travels around the sun in one orbit) is calculated, its orbital velocity can be determined.
The solar system, which includes our sun and all the objects that orbit around it, is also moving, and is located within the Milky Way, which revolves around the galactic center.
Scientists know that the Milky Way orbits around the galactic center based on observations of other stars, said Katie Mack, a theoretical astrophysicist at North Carolina State University. And if very distant stars appear to be moving, it is because the solar system is moving relative to the relative position of those distant stars.
To apply this concept to the Earth, Mack said: “If I start walking, I can say I’m moving because the buildings I’ve been through seem to be moving from front to back. And if you look at something further away, like a mountain on the horizon, it moves a little slower because it’s further away from buildings, but he is still moving relative to their location.”
By studying the motions of other stars relative to the sun, scientists determined that the solar system orbits the center of the Milky Way at a speed of 447,000 miles per hour (720,000 km/h).
Mack said that although everything is moving all the time, organisms on Earth don’t feel it for the same reason passengers on a plane don’t feel like they’re scurrying through the air at hundreds of miles an hour. When the plane takes off, passengers feel its acceleration on the runway and take off, and this feeling of heaviness is caused by the rapidly changing speed of the plane. But once the plane is flying at a specific altitude, passengers will not feel the speed of hundreds of miles per hour because the speed does not change.
Passengers will not feel the speed because they are actually moving with the same speed and direction, like an airplane. The only way passengers can notice their own movements and the movement of the plane is to look out the window at the passing landscape.
For humans standing on the surface of our planet, they do not feel that the Earth is revolving around the Sun because they are also rushing around the Sun at the same speed.
Source: Live Science