If there were a HUGE mirror in space, 10 light years away, and we had a VERY powerful telescope pointed at that mirror, would we see Earth as it was 10 years ago?
2007-01-25 19:51:32 · 7 answers · asked by Loman 2 in Science & Mathematics ➔ Physics
This is a hypothetical question of course. However, if you could do it, you would see the earth as it was 20 years ago. This is because it would take 10 years to get to the mirror and 10 years to come back to earth after reflecting off the mirror.
2007-01-25 20:01:24 · answer #1 · answered by Le Scientist 2 · 0⤊ 0⤋
no, we woudl see the earth as it was 20 years ago. If the mirror is 10 light years away, then the light would leave earth in say 2010. It would reach the mirror in 2020 and it would travel back from the mirror to us to see it in 2030.
2007-01-25 20:40:44 · answer #2 · answered by daddyspanksalot 5 · 0⤊ 0⤋
Nope. Twenty years. 10 years for light from Earth to get to the mirror, 10 years for it to be reflected back to Earth.
2007-01-25 20:01:08 · answer #3 · answered by Chug-a-Lug 7 · 1⤊ 0⤋
If we could see the precise image of what was reflected on that surface, yes, but we'd also have to deal with the relfection interfering with any such reading. In general, it'd take the exact image the full 20 years to get back to us.
2007-01-25 20:00:30 · answer #4 · answered by HaphazardJoy 4 · 0⤊ 0⤋
As a minimum 20 years, as light has to cover the distance twice.
2007-01-25 20:00:11 · answer #5 · answered by PragmaticAlien 5 · 0⤊ 0⤋
Makes sense to me.
One of the thought experiments Einstein used to do is imagine looking at a clock while moving away from it. As your speed of moving away approached the speed of light then the clock would appear to stop.
2007-01-25 20:05:12 · answer #6 · answered by modulo_function 7 · 0⤊ 0⤋
20 since it has to go both ways.
2007-01-26 02:22:01 · answer #7 · answered by Beach_Bum 4 · 0⤊ 0⤋