If light travels in light years......the earth is millions of years old?

ok so this random thought popped in my head.

if light takes so long to reach earth...and when we see the light years later the thing we are seeing has changed, moved or is not even there anymore. then if light from the other side of the galaxy takes so long to reach earth for us to see it..wouldn't this prove that prove how old the universe is? part 2 of the question....if a ship that traveled faster then the speed of light and when far enough fast enough to look back on earths (old light %26quot;if you will%26quot;) would we see what the earth looked like that amount of light years ago. and see the past %26quot;light%26quot;??
If light travels in light years......the earth is millions of years old?
%26quot;...if light from the other side of the galaxy takes so long to reach earth for us to see it..wouldn't this prove that prove how old the universe is?...%26quot;



Yes, it would *if* our galaxy was the entire universe, which of course it's not. By your reasoning, since light from the sun takes about 8 minutes to arrive on Earth, then that should enable us to know the age of the universe. In other words, the two scales simply aren't large enough. Instead we find the most distant objects we can observe and measure their distance. In this case, the most distant objects we can see now are some 13.7-billion light years away so we infer that the age of the universe is about 13.7-billion years.



%26quot;...if a ship that traveled faster then the speed of light and when far enough fast enough to look back on earths (old light %26quot;if you will%26quot;) would we see what the earth looked like that amount of light years ago. and see the past %26quot;light%26quot;??...%26quot;



Of course we can't travel that fast, but if we could then your reasoning is correct. In fact we could watch the launch of our spaceship.
If light travels in light years......the earth is millions of years old?
1. Don't understand what you mean

2. Yes
First part of your question? Looking at one galaxy in the universe isnt going to give the slightest hint as to how old the universe is as there are billions and billions of galaxies in the universe, some still here, some long since vanished! Your second question, Traveling at the speed of light, you would still be seeing the earth as it was when you left. You would need to travel faster than the speed of light to look back earlier than when you left which is theoretically impossible as you would turn into energy yourself at that speed.
Ooooh, Jesus is gonna be soooo angry at you for asking this question.



Earth was discovered my Sleestacks.
what about the 15 billion year old galaxies? Where are they now?
http://www.startrek.com/startrek/view/se鈥?/a>



http://en.wikipedia.org/wiki/The_Squire_鈥?/a>



http://memory-alpha.org/en/wiki/The_Squi鈥?/a>



http://www.imdb.com/title/tt0708478/



You'll have actually watch the episode all the way through.
Yes it would. That's why the farther away objects are, the light they give off has been redshifted because the acceleration between us has increased.
first of all light isnt travelling in light years it travels in km per second per second which is arround 300,000 km per second per second light years is a measure of distance not speed averagely the light of the sun takes 8 mins to reach the earth which means the light we are seeing from the sun is 8 mins ago.so your theory was right if we travel far enough from our solar system ex. 4 million light years away that would be 300,000 km x number of seconds per year = 1 light year x 4 million would be equal to 4 million light years. if we look back to our solar system, we would see the solar system 4 million years ago (if we can still see our solar system that far). not only the past light but it is like time traveling. you can see the old earth 4 million years ago
If you're trying to say that the constant speed of light gives us an indication as to the age of the universe, you are correct, but this has been known at least since the time of Einstein. We know that the universe can't be older than 13.7 billion years, because we can't see any objects more distant than 13 or so billion light years away.



Secondly, we have things like radiometric dating that give us a very accurate age for the Earth, and it is billions of years old - 4.5 approximately.



Thirdly - yes, if you %26quot;could%26quot; travel faster than light, you overtake light that left our planet many years ago. You could go to a point in space and, assuming you had a powerful enough telescope, look back at Earth as it was.
%26gt;If light travels in light years......the earth is millions of years old?



That's right. In fact, it is 4.5 billion years old. That's over four thousand million years old.



%26gt;then if light from the other side of the galaxy takes so long to reach earth for us to see it..wouldn't this prove that prove how old the universe is?



You'd think so. Actually things are a little more complicated than that. The light that is reaching us from the farthest distance away is actually reaching us from FARTHER than it should if you just go with the current size of the Universe and the speed of light. In other words, the radius of the observable universe is larger than the age of the Universe should allow. The reason for this is that the Universe has been expanding over time. We know this because light from distant objects is redshifted in accordance with the distance of those objects. By looking at the pattern of this redshift over different distances, we can work out the actual age of the Universe (or at least, the amount of time that has passed since the first observable galaxies came into existence; however the two aren't that far apart from each other and we can easily extrapolate between them). In any case, the Universe is about 13.7 billion years old.



%26gt;if a ship that traveled faster then the speed of light and when far enough fast enough to look back on earths (old light %26quot;if you will%26quot;) would we see what the earth looked like that amount of light years ago. and see the past %26quot;light%26quot;??



No. The principle of Einstein's special relativity is that a light beam will always appear to move at the same speed. So no matter how fast you were traveling away from the Earth, the light coming from the Earth in the same direction as you would always appear to be going PAST you at that same speed. This is because as you go faster, time for you slows down relative to the rest of the Universe. If you were to go faster than light, the light from the Earth would STILL appear to be going past you at the same speed, because time for you would actually be going backwards. Incidentally, traveling faster than light is impossible.
well earth is very very old and the second yes