how long does it take to see a star's light?

Question

what does light years mean?

Answer 1

The time to see a star's light depends on how far away it is. A light year is the distance light travels in one earth year. Since light travels at 186,000 miles in a second and there are 31,536,000 seconds in a year, light travels 5,865,696,000,000 miles in one year. The closest star besides our sun is 4.4 light years away. That means the light you see from that star is 4.4 years old.

Answer 2

Distance(miles) light travels [in a vacuum]...

per second: 186,000
per minute: 11,160,000
per hour: 669,600,000
per day: 16,070,400,000
per year: 5,865,696,000,000
or 5Trillion, 865Billion,696Million miles

Now why you want to know that distance is beyond me since very very very few people can truly grasp the sheer immensity of those numbers and distances. I can talk about and throw around those numbers all day, but I can't truly put them into perspective. They're just too huge. I mean, what's the longest trip you've ever made...a thousand miles or maybe two thousand even? that is nothing compared to cosmic distances.
Anyway, it takes time for light to travel anywhere, just like anything else. So, depending upon how far away a star is, it took that long for the light hitting your eyeballs to get here from the star. Alpha Proxima is 4.5 light years away. When you look at it, the photons hitting your eye left that star 4.5 years ago. Something to think about: You're not even seeing the star where it is. In those intervening 4.5 years, it moved and so has the earth. So, what you are REALLY seeing is a photon that was sent from its THEN position in a direction that ended up intersecting with the earth's NOW position. But, it's all perfectly okay in a relative way.

Answer 3

Stars are in different distances from us. Some of them are nearer and some of them are farther. The more distant the star is the longer it takes for it's light to be seen from the earth. Light year means the distance that light can travel in one year. So do not get confused. Light year has nothing to do with time; it is a unite of distance.
Some stars are many light years away from us that it takes a lot of time for their light to reach us, and that's why new stars are being found even today.
The amazing part is that sometimes astronomers find a star that they say it might have died now, because we are getting a light that was sent out billions of years ago!
In fact our science of astronomy is about past! It means that we are observing the past life of a star and other objects.
An example could be that if some people would look at the Earth from a very object distance in universe it is possible that they would see dinosaurs because the light from the Earth had traveled billions of years to reach them!

Answer 4

Depends how far away the star is. If it is close (the closest is Alpha Centauri), then it can take as little as 4 years. It can take hundreds of millions of years, for the far-distant stars. The light from the sun takes something like 8 minutes to get to the Earth. A light year is the distance that light travels in a year. (I don't know the actual number of km or miles.)

Answer 5

Don't they teach anything in school anymore?? A light year is the distance that light travels in one year. The time it takes for the light from a star (or any object) to reach your eye depends on how far away the object is.

Answer 6

Ta Daaaaaa....All the answers on time are correct. From 8 minutes to hundreds of years, light reaches us from a star. Since they are correct and I cannot answer it any better....time for "Logic's Logic"

Light is not the only thing traveling at the speed of light. Electromagnetic energy, of which spectrum light belongs, also travels at the speed of light. Radio waves travel just as fast. (for those that dont realize radio waves are electromagnetic energy) Since "c" the speed of light is constant, and the fastest speed known, Star Trek fans may remember the logrithmic value to Warp speed. Since faster than light was available, how did they communicate with Star Fleet? Hence ( I like that word) Hence was born "Sub Space radio". Radio communication that could travel faster than Warp Nine. Tune in again when all answers are good and all I can give is "Logic's Logic !"

Answer 7

A light year is the distance traveled by light in one year.
And the time taken to see a star depends on its distance from Earth & this distance is measured in light years.

Answer 8

299,792.458 km/s is the speed of light. So, it would depend how far away the star is as to how long it would take to see the light. I apologize, but this is as accurate an answer you can depend on, unless you want to repost the question to ask what particular star to which you are referring.

Answer 9

specific. as quickly because of the fact the final photon arrives, then the superstar will not seem to us interior the nighttime sky. it ought to be 10 years after that photon left the exterior of the superstar, or this is 5,000 years. yet do not anticipate any stars going away any time quickly. because a guy or woman's lifetime could be eighty years (+/-) and a superstar's lifetime is measured interior the billions of years, the opportunities are very low that any given superstar could have "long gone out" in the time of that element. additionally, stars do not purely turn off easy a easy bulb. the top point for a superstar could be the two cataclysmic - as in an excellent nova, or boring, as in transforming into some low power form of dwarf superstar. the technique of eating each and all of the the rest gasoline and fairly turning darkish is a very long one - a minimum of in human words.

Answer 10

That's an interesting question. Light travels at 300,000 kilometers per second or 186,000 miles per second. The time it takes for light from stars to reach us is the distance to the star divided by this speed. The nearest star to us is the Sun and it takes about 8.3 minutes for its light to reach us here on Earth.
Other stars are so much farther away that it is convenient to express the distance to them in units of the distance traveled by light in one year. This unit is called a light year. The next closest star to us is Proxima Centauri. This star is 4.3 light years away which means that light from it takes 4.3 years to reach us. Our galaxy is about 100,000 light years across. This means that it can take tens of thousands of years for light from some stars in our galaxy to reach us. For stars that we can see in nearby galaxies it can take millions of years. The farthest objects we can see are quasars. They are so distant that the light we see from them today left billions of years ago.

So when we look up at the stars we are looking back in time. This is useful for astronomers because when we look at very distant objects we can see what the Universe was like a long time ago.