From a 100% stationary observer existing outside our Earth, solar system, and galaxy, how fast would a person standing on the equator be traveling through space?
Earth's equatorial rotational speed is 1041.666mph + Earth's orbital speed around the sun is 66,660 mph + .... + .... = ?
I guess I need to learn how fast the solar system rotates/orbits within the milky way, and how fast the milky way rotates/orbits within the entire universe, to get the final answer.
2006-07-20 10:05:00 · 5 answers · asked by Finar C 1 in Science & Mathematics ➔ Physics
Speed is only a meaningful concept in physics if you specify a reference frame! (That is, you need to pick an observer that you think of as being stationary.)
There is no special reference frame which is "stationary" compared with the universe. This concept is called Galilean relativity. See http://en.wikipedia.org/wiki/Galilean-Newtonian_relativity
2006-07-20 10:17:05 · answer #1 · answered by Aaron 3 · 0⤊ 0⤋
It all depends on the reference frame, as other responders have noted. The rotational speed and orbital speed is meaured in a frame tied to the sun. The rotational speed of the galaxy, with respect to a frame stationary with respect to the average of nearby galaxies, depends on the distance to the center of the galaxy but I have heard the estimate of one rotation in 250 million years, more or less. That is also an estimate of the solar system's revolution time about the center. It is estimated that we are about 30,000 light years from the center, so you could figure out a revolution velocity from that.
2006-07-20 19:03:17 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Estimates for the galactic velocity are on the order of 220 km/s. Total velocity relative to the speed of light is around 320 km/s. I just read some paper where they verified this through muon flux from the ionosphere. Of course part of the total absolute velocity is the galactic orbital velocity. So, yes, you really are traveling at one thousandth of the speed of light already.
The question of universal rotation is moot. How would we know? There is no reference frame to observe it. And no great central mass of the universe that we know of.
2006-07-20 17:14:03 · answer #3 · answered by Karman V 3 · 0⤊ 0⤋
It still wouldn't help--we're all 100% stationary (in the way you're using it) from our point of view. Speed is always relative to the observer unless you're talking about the speed of light through a vacuum. Just because you're outside of the galaxy doesn't mean you're outside the theory of relativity.
2006-07-20 17:20:48 · answer #4 · answered by Pepper 4 · 0⤊ 0⤋
Speed is relative. It changes base on the frame of reference. So it is pointless to be trying to calculate some absolute speed. Choose a frame of reference and one can get some very high speeds.
2006-07-20 17:19:41 · answer #5 · answered by gklgst2006 2 · 0⤊ 0⤋