When most stars die they form objects calle white dwarves. These will continue to emit light for trillions of years before cooling into black dwarves. This is older than the current age of the universe.
Because 1) they are very bright, most of them are bigger than our sun 2) light travels very quicky when you look at them, you are looking at the star about hundreds of millions of years ago, as that is how long it takes for the light to get to here.
The distance to stars is measured in light years, which is the distance light travels in one year. The stars we see in the night sky are typically several light years away, with the closest star to Earth, Proxima Centauri, about 4.24 light years away.
The nearest star (other than the Sun) is 4.7 light-years from Earth, meaning it takes 4.7 years for light from that star to reach us. That star could die and we would not know it for 4.7 years. Some stars are billions of light years away, it would be billions of years before we noticed that the star was no longer shining.
i cant say because the little dipper is made op of many differt stars and alls 7 stars r different light years away. 4 example, the star kochab is 126 light years away and the star pherkad is 480 light years away.
According to SIMBAD, ~970. But there's a lot of stars within 50 light years whose distances aren't known. There's quite a few stars within 50 light years. To get a good estimate, we should consider how many stars within 20 light years, and go from there. The nearest 25 light years are really well catalogued, and the current census is 200 stars. Now, through knowledge of Geometry, one can say that if you multiply the radius of a 3D shape by a number, x, the volume will increase by the x^3. Why 3? because it's a 3D shape. So we double our sphere from 25 to 50 light years. So thus the volume increases by 2^3 = 8 times! So there are 8 times as many stars within 50 light years as there are within 25 light years. 200 * 8 = 1,600 stars (estimate).
Stars are not measured in light years. The distance between them is.
The light from the stars travels billions of years. Most of the stars we see are already gone, but the light from them us still traveling.
Light Years.
because the stars are very far away so the astronomers use light years
Because 1) they are very bright, most of them are bigger than our sun 2) light travels very quicky when you look at them, you are looking at the star about hundreds of millions of years ago, as that is how long it takes for the light to get to here.
The distance to stars is measured in light years, which is the distance light travels in one year. The stars we see in the night sky are typically several light years away, with the closest star to Earth, Proxima Centauri, about 4.24 light years away.
in light years
This varies widely, between about four light-years for the nearest star (after the Sun, that is), to billions of light-years for stars in the farthest observable galaxies.
1.5 billion stars per 1000 light years.
Light years
The stars are upwards of 4.2 light-years from the Sun.
The three stars that compose the hunters belt in the constellation of Orion are: Alnitak, Alnilam and Mintaka. They are 800 light-years, 1340 light-years and 915 light-years away from us respectively (but, of course, from earths perspective they are in a neat line).