Why do some stars you see in the sky did not exist ?

Question

Did the lights haven't reach the earth ?
bonikingv

Answer 1

Because it can take hundreds, thousands, even millions of years for the light from stars to reach earth. That means that anything that happened in the past would not be seen for millions of years.
So, yes, the light hasn't reached earth. When we look at stars in the sky, we are essentially looking at how they used to be.

Answer 2

A Star that does not exist would not be seen in the sky =the reason is that it does not exist.
If a star is burnedout it would no longer radiate light and would no longer exist as a star.
Light from star exist because stars exist. And the velocity that light come from a star has never really been exactly determined or proven to any degree of certainty,except relativistically some stars are further away than others.The reason is that the Nature of light has never been completlely Understood . The Big Bang theory indicates that light during creation moved in an instance of time of 10^-43 seconds and traveled a phenomenal distance in just that short time. So we are not exactly sure how long it takes a starlight or other cosmic lights to reach us.Science can only deternine relative velocities because they cannot locate an absolute center where all motion is relative to, in the Universe.
One way to look at it =is "what you see is what you get."

Answer 3

Even though light travels very fast, in the expanse of the universe, light speed just isn't that fast.

Some stars are so far away that light, traveling at 186,000 miles per second takes years to get here where we can see the image of a star. Heck, the Sun's light takes 8 and 1/3 minutes to get here on Earth.

If a star were 100 lightyears away (a distance of 100 times the distance that light would travel in one year), then if it suddenly blew up, we would not see the event for 100 years.

Since stars are not suddenly and spontaneously born, we see gradual increases in the light output from stars that are beginning to coalesce and shine.

Answer 4

Do you mean why is it that some stars which do exist in the nightsky cannot be seen by the naked eye? You're right in that they may not be bright enough or near enough for us to see them clearly. Since the Earth tilts so that we have seasons, it is also a reasonable explanation that some stars you see at the beginning of the year may not be seen later into the year. Also depending on the darkness of your stargazing surroundings, you may see more or less stars - Many of the stars are drowned out by the urban lights. Stars close to the moon may also be drowned out by the moon's radiance.

Answer 5

I think I know what you're asking, though you worded it oddly.

"The light you are now seeing is around 25,000 centuries old and began its journey around the time of the dawn of human consciousness," says Joe Rao, SPACE.com's Night Sky columnist. "When it began its nearly 15-quintillion-mile journey earthward, mastodons and saber-toothed tigers roamed over much of pre-ice-age North America and prehistoric man struggled for existence in what is now the Olduvai Gorge of East Africa."

Check my source link for a bit more information. Basically, the light takes so long to make it to us visibly, that those stars we see are already gone. It's like watching something in some really slow-motion. I'm sure one day the sky will have a big explosion in it, and that will just be us catching up with the visuals of when some star or another exploded tons of years ago.

Answer 6

Stars brightness travel at the speed of light 186,000 miles per second (I think).

Some of the stars we see are so far away the time it has taken for the light to travel to earth has exceeded the life of it.

Answer 7

i guess the lights didn't reach earth, but weren't stars determined by the dimness, and the color?

Answer 8

Because by the time you see them from earth they have already burnt out.

Answer 9

good question for my science project