How fast earth moving

Dizzy yet? Well hold on. The Milky Way itself is moving through the vastness of intergalactic space. Our galaxy belongs to a cluster of nearby galaxies, the Local Group, and together we are easing toward the center of our cluster at a leisurely 25 miles a second. Each of the motions described above were given relative to some structure.

Our motion about our sun was described relative to our sun, while the motion of our local group of galaxies was described as toward the Great Attractor. The question arises: Is there some universal frame of reference relative to which we can define the motions of all things?

In , the COBE satellite was placed in orbit about the earth again, the earth is the frame of reference! This radiation, which remains from the immensely hot and dense primordial fireball that was our early universe, is known as the cosmic microwave background radiation CBR.

The CBR presently pervades all of space. It is the equivalent of the entire universe "glowing with heat. Because the CBR permeates all space, we can finally answer the original question fully, using the CBR as the frame of reference. The earth is moving with respect to the CBR at a speed of kilometers per second. If she looks at something more distant, like a mountain on the horizon, it moves a little slower because it's farther away than the buildings, but it still moves relative to her position.

Then there's the entire Milky Way, which is pulled in different directions by other massive structures, such as other galaxies and galaxy clusters. Just like scientists can tell that the solar system is moving based on the relative movement of other stars, they can use the relative movement of other galaxies to determine how fast the Milky Way is moving through the universe.

Even though everything is moving all the time, living organisms on Earth's surface don't feel it for the same reason passengers on an airplane don't feel themselves zipping through the air at hundreds of miles an hour, Mack said.

When the plane lifts off, passengers feel the plane's acceleration as it speeds down the runway and lifts off; that weighted feeling is caused by the plane's quickly changing speed. But once the plane is flying at cruising altitude, passengers won't feel the speed of hundreds of miles per hour because the speed doesn't change.

The passengers won't feel the speed because those passengers are actually moving at the same speed and direction, or velocity, as the airplane. There's no relative motion — everyone sitting on the airplane is moving at the same speed as the airplane itself. Travelling at the same speed means we cannot feel the spin. It is like driving a car. Only when you change speeds do you notice you are travelling, like putting your foot on the accelerator or making an emergency stop.

A change in speed has been happening here on Earth, but it is far too slow to notice.