When we look at the stars are we actually looking back in time?

Question

Well, if it takes thousands of light years for a twinkle of light from a star to hit our eyes here on earth, then a lot of time must have passed when that ray of light was traveling towards the earth right? So, when thinking about it, when I look up and see a twinkle of light I am actually looking back in time, aren't I?

Answer 1

Yes, this is correct. But it is not an unusual phenomenon. During a thunderstorm, the sound of the thunder takes longer to get to you than the light does, so you hear the thunder several seconds after you see the lightning. Echoes work the same way: you can hear the delay caused by the fact that sound takes time to travel. In a sense, you are 'hearing back in time'.

Now, we usually do not see a 'light echo' because light moves so fast, but it does take time to move. Sometimes you can hear a difference on a phone if you are making an international call where the signal goes up to a satelite and back down to earth. Again, the delay is very short (less than a second), but it is there. For the sun, the delay is a bit more than 8 minutes. For stars it is several years to hundreds of years for the ones we see without telescopes. For more distant galaxies, the delay can be millions or billions of years.

Answer 2

Stars are just the suns of far off galaxies. They are roughly round, as thier own gravity pulls them into this shape, but you can't see the colour/texture of the surface very well as they are basicly big balls of burning gas, and you'd burn wayyy before you were close enough to see (or a probe was close enough to see). I think stars are quite interesting. They have a cycle, from birth to death and everything, and most of the atoms everything on Earth are made up of (including us) were at some point in a star, which went into supernova and the atoms exploded out.

Answer 3

No. People are easy to say "yes" because they're all trained to believe everything they read in books especially popular books , like "bibles" or "science books" (both published by the same groups by the way). Shin a flash light at something... the wall, now turn it off. When you turned it off did the beam of light suddenly "shut of" from the flashlight and begin traveling toward the wall? ...NOoo! It TURNED OFF...THE LIGHT COMPLETELY WENT OUT , the second , it was switched off. Now "Light ,and, source of light" are two different things.

Electricity is same. does lightning come from above or below? BOTH. The protons and electrons must be on both sides to conduct. When they deplete , it shuts off the bolt all at once. JUST BECAUSE you don't see the light of a bolt of lightning yet...does not mean the current is not there. you can still get fried even with no visible light from the lightning.

Now, when you say "back in time" ... what IS time? ...Its how you see the earth rotate and revolve around the sun. ...that has changed GREATLY over earths existence. and the universe is older than earth ,or its sun. Which says your concept of time is not only selfish , but only relative to YOU , and your current moment of existence on this planet.

You do not get the privilege of turning back time. Mistakes are needed , to learn from. Therefore a necessary evil. You choose to do right , or do wrong - even when thinking you're doing right...problems occur...how do you handle it? is the true test - either lie in the mistake , or get out of it. - ...choices... its all about choice.

And for a scientist to consider it (turning back time) , is equivalent to a christian who says Jesus is God when the book clearly shows Jesus saying he is NOT. (MANY TIMES !)
...although Jesus did not write the book himself.
...Its silly pipe dreams and a failure to read thoroughly. Simply put.

You are not witnessing "millions of years ago" , you're watching it live.

Answer 4

Yes!
Even as I look at my computer screen I am seeing it as it was in the past. Think of how when you see somone clap their hands from a distance, there is a delay in the sound because light travels faster than sound. The same is for light but of course we have no way of sensing the delay because the speed of light is the fastest anything can go, according to Einstein.

Answer 5

You are correct. That is why we can define the Observable Universe as having a limit of 15 billion light years. If there are stars beyond that, in the entire existence of the universe, that light would still not have had time to reach us. And any body receding from us at the speed of light, will never appear to us.

Answer 6

Like everyone has pretty much said, the answer to your question is yes.

paraphrased from Alan Parsons' Time Machine album Track 2:
"When you look into the night sky, you're seeing the stars because of the light that travels from them to you. It takes time for that light to reach you. Imagine you're looking at a star that is say 6,000 light years away. You're seeing that star as it was 6,000 years ago. Now imagine someone at that star looking at us. They'd be seeing us as we were 6,000 years ago. Which of those two is "now"?
So, space and time are connected. As you look out across space, you are looking back through time."--some British Univ astro prof. [Sorry but I forget who it says was used for the narrative.]

Answer 7

yes you are, when you look at a star like betelgeuse that is actually 540 light years away you are seeing it as it was 540 years ago.

even the sun when you look at it you are seeing it as it was 8 minutes ago. if it blew up you would not know for 8 minutes.

the moon is about one light second away. so you see i9t as it was one second ago.

something neat to think about

Answer 8

yes

Answer 9

Yes.

Answer 10

Yep, everything is relative to light.