does that mean it also happened hundreds of years ago?
so its possible that what we're seeing now has long been gone?
2006-10-18 17:04:16 · 16 answers · asked by knuckle curve 1 in Science & Mathematics ➔ Astronomy & Space
You're absolutely correct.
In fact, you may even be looking at a star that doesn't even exist anymore - but you are seeing the light that it emitted hundreds or thousands of years ago!
2006-10-18 17:09:39 · answer #1 · answered by LeAnne 7 · 1⤊ 0⤋
Yes, and here is an interesting fact:
You probably know that "Light Year" is a measure of distance, not time. It is the distance (number of miles, for example) that light travels in one year. So if we are looking at the nearest star, which is four light years away, we are actually seeing it as it was four years ago.
When astronomers see a nova (exploding star) that is say, ten thousand light years away, the star they are looking at is long gone. It actually exploded 10,000 years ago!
Now the interesting fact: Our own sun is 8 light minutes away from earth. That is just another way of saying that it takes the light from the sun 8 minutes to reach the earth. SO... If our sun suddenly went out, or even exploded, we wouldn't even know it for eight full minutes!
Our sun may have exploded six minutes ago! If it did, we wouldn't even know it for another two minutes! (But don't worry, it didn't... astronomers know enough about exploding stars to know that it won't happen to our sun until a few billion years from now.)
2006-10-18 19:05:38 · answer #2 · answered by Don P 5 · 0⤊ 0⤋
It stems from one of Einstein's postulates, basically - The speed of light is the same for all observers. In your normal world, a bullet traveling 1000 feet per second would travel 0 feet per second relative to someone traveling 1000 feet per second. Light does not behave this way. Light will always measure at the speed of light no matter what speed you travel. If this doesn't sound strange to you, you are missing the concept. This idea should go against your concept of normal because the idea will change how you view the world. How can someone traveling near the speed of light measure a photon with the same results as someone sitting still? The way this happens is - speed is distance divided by time. Therefore distance and time have to changes relative to the speed of light. They are not absolute as you grew up knowing, the speed of light becomes the absolute and space and time around it is varying. Your watch, as viewed by your friend on earth, slows down as you travel at high speed relative to earth. Your time is slower and you will age slower. I had better stop now...
2016-05-22 01:16:53 · answer #3 · answered by Megan 4 · 0⤊ 0⤋
Sited, cited, sighted, and syted are all words to describe your answer. A
distance for instance, a vision we will say one had to sit and stop, gather
data and make selection is a possible environ of space over spatial color.
The general package of a simteleradiance scope on space. This part of
a siting, we would call a flash or a photo, perhaps a vision area. Now the
question is this a signal. In order for you to see something in the past
or the future would have a sender, a source that uses symbols or
colors, info or data that you actually intellectually recognize. So it is now.
Now meaning that you cannot hold, participate, change or reduce what
you see in this type of vision. The event is partnered to your reception.
2006-10-18 17:15:01 · answer #4 · answered by mtvtoni 6 · 0⤊ 1⤋
Yes if the light is very much brighter and no if the light is not vissible to our eyes.But some instruments can detect that one in the form of raditations like cosmic rays.If we discover the space craft that move in a velocity of 100C(velocity of light) we can observe an event in the universe in some period of time.
2006-10-18 17:14:27 · answer #5 · answered by sunstarsunil 2 · 0⤊ 0⤋
Yes in fact a lot of the stars we see today dont exist anymore. We could see a supernova and it happened before our solar system was born. The light starts its journey at that time but it doesnt reach us until now.
2006-10-19 13:10:13 · answer #6 · answered by Anonymous · 0⤊ 0⤋
yes it does, you are exactly right!
everything we see happened before we see it because we have to wait for the light to reach our eyes, here on earth everything is so close that time is negligible, as the didstances grow the light travel time lengthens eg, reflected light from the moon takes ~1.3 seconds to reach us and the suns light takes ~8 minutes, this means if there was an explosion on the moon, 1.3 seconds after it happened we would see it, similarly, any solar flare is observed here on earth 8 minutes after it actually happened, this exends to events such as supernovas which can happen thousands of years before we here on earth know anything about it.
2006-10-18 22:35:49 · answer #7 · answered by jen_82_m 3 · 0⤊ 0⤋
That's right! If you look up at the night stars you are looking back into time as far as the most distant object you can see. If you look at the Galaxy Andromeda - you are looking back about 2.2 million years. That means that the the light reaching your eyes today left that galaxy about the time man started walking erect on earth. Pretty awesome.
2006-10-18 17:10:02 · answer #8 · answered by Anonymous · 0⤊ 0⤋
Yes, that is why they say looking through a telescope is looking back in the past.
Technically this is true of anything you look at. When you see a person across a room you are seeing them how they were a few nano seconds ago.
2006-10-18 17:15:01 · answer #9 · answered by minuteblue 6 · 1⤊ 0⤋
Yes
2006-10-18 17:06:44 · answer #10 · answered by Anonymous · 0⤊ 0⤋