If I lived a 100 light years away but could see the earth clearly, would I be seeing 100 years into the past?

Question

So if I lived on another planet a 100 light years away but had a really powerful telescope. I aimed it at earth and could see everything really clearly like people. However would I be seeing everything a 100 years ago due to the amount of time it takes light to get to the planet?

Answer 1

Dear Sir:

I understand your question, but need to point out that Planets do not shine (They reflect some amount of light from their Star). At the distance of 100 Light Years (100 LY) you would only be able to see our Sun, and its brilliance would blind you from seeing the other planets which circle around it, especially the smaller ones. Jupiter, Neptune, or Uranus might be detected by a flicker in the Sun's brilliance as that
particular planet passed between the Sun and you, the observer.

However, all corrections aside, were you to be looking at our Sun, 100 LY away, the light you saw would have been emitted by the Sun 100 years ago, by definition. You would not be able to see any people as you mentioned. I guess you could say that you were looking into the past. 100 LY is a very long distance away.

Answer 2

It might seem like the past before photography is lost forever, but it really isn't.

I once read that if it were possible to go faster than light, or build a warp drive or go through a wormhole, and use it to carry an 8,000 mile wide telescope 231 light years away to the right position you would actually be able to catch up to the light emitted by John Hancock 84,000 days ago and use what little remains of it to make an image of the real signing of the Declaration of Independence (but only if it was done outside, on a roof, in a room with a window, or in a room with a skylight)


Requirements:

1 telescope the size of the Earth, accurate to 0.00005 millimeters
1 warp drive
1 artificial gravity generator (to prevent the telescope from collapsing under it's own self-gravity into a molten, glowing, artificial glass mass.

Answer 3

1. You can see things because light from those things has entered your eyes. It takes time for that light to get to you. The light that reaches your eyes may have been traveling to you for a long time, so you may see things as they were a significant time in the past. There really is no simpler way to explain this. 2. Are you actually asking if the planet Earth exists? Think about this carefully. You can verify that the planet Earth exists in other ways than looking at it. It takes light almost no time at all to travel from the planet Earth to your eye, because you're standing on the planet Earth. 3. The Sun did not exist when the universe began. The universe began around 13-14 billion years ago; the Sun has only existed for about 5 billion years. I'm not really sure what you're getting at with the rest of your question. 4. If these hypothetical scientists are 100 light-years away from Earth, they're seeing Earth as it was 100 years ago, because the light from Earth takes 100 years to get to them. Here's another way to think about it. Let's say you live in London and I live in Paris. I write you a letter saying: "Right now I'm eating a sandwich". It takes that letter two days to get to you. So, two days later you open the letter and read my words. When you read that letter, am I eating a sandwich? No, I ate that sandwich two days ago, but you're only hearing about it now because it took two days for the letter to reach you. Light works the same way, though it travels much faster than even the most efficient postal system. Light is carrying information about something, just like the letter, but because it takes time to get to you, that information may be out of date when you see it.

Answer 4

Yes. This is because light takes 100 years to travel from Earth to that planet. Light travels about 9.83 trillion kilometres a year. Anyway, if you were that far away, even with an extremely powerful telescope, you would probably be unable to see Earth because it does not emit much light.

Answer 5

Although I dbout the capabilities of the telescope, yes, you would be seeing 100 years in the past; the light from the earth would be 100 years old.

Answer 6

Hi. If you mean you were 100 light years away NOW and looked at Earth then you would see it as it was in 1907.

Answer 7

Yes.

The same thing happens with sound, though. If you hear something far away, you are hearing how it was in the past. That is why you see a lightning strike before you hear the thunder: sounds goes slower than light. The time difference is only a few seconds, but the ditance is smaller.

For stars, there won't be sound, but the light takes years to get to us.

Answer 8

yes you would see the earth the way it was 100 years ago. because even though light travels really fast it still takes time to travel over distance.

Answer 9

Yes if you lived 100 light years away and put up a giant radio dish to listen to radio stations from earth you would not hear anything because there was no radio in 1907.

Answer 10

absolutely yes, irregardless of the power of the telescope. it still takes light to travel the 100 light years, and the light is what you are actually seeing.