Is it possible to view earth's past?

Only if the construction was completed before the light arrived - do not contract the Wembley stadium group - HA HA -- HUMOUR?

 

Log in or Sign up to hide all adverts.

Maybe if we could capture light that has been bent by the gravity of stars and turned back towards the earth, I wonder if there would be to much decomposition to create an image, it would be possible to see different dates by finding shorter and longer paths.

 

Log in or Sign up to hide all adverts.

yama

Let�s talk about 1 hour past not years. The speed of light is about 671 million miles per hour, when we see Saturn which is about 830 million miles from the earth it mean we are looking at Saturn past something about 1 hour and 15 minutes past. so from Saturn we can see the earth the same.

 

Log in or Sign up to hide all adverts.

The real problem is that you wouldn't see much anyway. We can't see individual planets outside of our solar system. The nearest solar system to Earth is roughly 4 light years away. We can see the star but we are only looking at a point of light and not at the actual surface.

If there are any planets in that solar system we can't see them either. So, "seeing" Earth from 20 light years out wouldn't be possible or rather it wouldn't be any more possible than seeing a planet in a solar system 20 light years away from us currently is.

 

light is affected by gravity

 

Possible, but there are a lot of extremely challenging requirements to make it happen. First of all, the mirror would have to be transported far enough, and it would have to go to a location at a speed much faster than the speed of light. Second, if you were to adjust the co-ordinates to make it change what time to see the Earth, the transmission would also have to be a lot faster than the speed of light and the change in coordinates would have to account for the speed of transmission to be accurate. Then, it would have to adjust its position, in a straight line relative to Earth, at a speed much faster than the speed of light. The resolution of the mirror would have to account for the position of the mirror relative to its speed and the speed of light (for us to actually "see"). That is already hard, if you want the "zoom" to be static", but a lot harder if you want to be able to adjust the zoom. Finally, all hell breaks lose if you take into consideration all of the other celestial bodies floating around there, when adjusting the position of the mirror... it would have to account for those objects as well, in order to not collide.

Theoretically, you could also make a mirror that can be placed anywhere in the universe, so instead of only having the option of looking at one position on Earth, you could have a full 41250 degree positioning to look anywhere on Earth at any point in the past. No wonder it is hard to find life in the universe...

PS: of course, this would all require technologies that are far far more advanced than we have today. And one should ask if the utility of the tool is worth the investment... I won't get into the economics because I don't think it would be that useful.