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Curiosity about our Universe

by shinnsohai
Tags: earth, solar system, speed, universe
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shinnsohai
#1
Mar24-13, 10:16 AM
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As you may know, our planet(Earth) , solar system, galaxy are moving in a very fast speed travelling around the universe
but, whenever a satellite being launched out from earth, and it's stationary means no speed
then will it be left behind ??
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mfb
#2
Mar24-13, 10:33 AM
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There is no absolute velocity in the universe. Only velocities relative to something else.
Satellites start with zero velocity relative to the earth and gain a small velocity (~8km/s) relative to it - just enough to orbit it. Therefore, they stay in an orbit around earth. The speed of (earth+satellite) relative to anything else does not matter.
shinnsohai
#3
Mar24-13, 11:05 AM
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P: 33
this seems interesting !!
so even we're in stationary, we're moving with 8km/s
cool!

Okay my curiosity solved !
:D

mfb
#4
Mar24-13, 11:12 AM
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Curiosity about our Universe

Quote Quote by shinnsohai View Post
so even we're in stationary, we're moving with 8km/s
cool!
Much more, depending on the view. Earth is moving around the sun with 30km/s (relative to the sun). The solar system is moving around the galactic center with ~200km/s (relative to the galactic center). Relative to the cosmic microwave background, we are moving with ~400km/s.
Relative to high-energetic cosmic rays, we are moving with more than 99% of the speed of light ;).


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