2007-02-21 09:59:09 · 5 answers · asked by goring 6 in Science & Mathematics ➔ Astronomy & Space
If you are referring to "proper motion," the apparent motion of a star against the background of space...then your assumption is incorrect. In fact, we can measure the motions of stars moving across the sky...it's just that the motions are very slow.
One of the fastest moving stars in the sky is Arcturus...it has moved 1.25 degrees in the last 2000 years. That's about 2 1/2 times the visual diameter of the moon.
2007-02-21 10:30:36 · answer #1 · answered by Anonymous · 0⤊ 0⤋
Assuming it is not travelling directly at or away from us, the star will exhibit motion. It's just that the differences involved are so vast that the motion can only be observed over long time scales (i.e. months and years).
2007-02-21 10:03:56 · answer #2 · answered by davidbgreensmith 4 · 0⤊ 0⤋
Think about looking at a plane in the sky. It appears to move very slowly but is actually travailing at 100s of MPH. This is because it is far away. Stars are enormous distances away so they don't appear to move at all, but they are.
2007-02-21 10:07:52 · answer #3 · answered by Jon H 2 · 0⤊ 0⤋
Ever been driving and the trees close to the car appear to be moving faster than the ones farther away? Same concept, except the distances we're talking about here are thousands of lightyears. They do move but it takes longer periods of time to notice.
2007-02-21 10:07:14 · answer #4 · answered by constantine3885 1 · 0⤊ 0⤋
they do its called red shift first observed by Hubble
2007-02-21 10:08:30 · answer #5 · answered by Anonymous · 0⤊ 1⤋