if the stars are thousands of light years away?

Question

how do we know they are still there? they could have gone by now

Answer 1

Good question, I think its because we use doppler shift which tells us how old the star was when the light had arrived on earth. Judging by the age of the light we can then make informed assumptions about its current status, if its towards the red end of the spectrum its old and towards the blue end it relativley new light.

Answer 2

Yes, your thoughtfulness, you are right - how can we be sure that radiant starts we see are still there? This brings tears into my eye already, but tears, dear friend, can be no good a compensation for the countless brightly stars lost on firmament as mist in the passing of time. Every time we look up into heavens above, we wonder upon the act of creation - we think of God, His powers and beauty. During hot summers, I use to sleep on the roof of my house under a starry sty. I used to look at stars for hours; the Moon and the ambience mist of the Milky Way were to me, as a little boy, the most generous gift of nature the value of that I could not even imagine at that time. And now, those scientists can tell me that this might already be dead. But I am resilient, and I 'rage at the dying of light'. I would say instead - if the stars I see were no longer there then would not be countless new stars there in place of the old ones, even more radiant, wonderful? And would not there be yet more, born at the time when I gazed avidly into the skies, to illuminate heaven above for many long years to come?

Answer 3

Yes some stars are gone a long time ago and how can they shine on our future while the ones which are there now, we will never know about it as we will be gone for a long time. Is not that a funny trick of Time!

Answer 4

Even the shortest lived stars would survive for around a million years. Since there is an information lag (omicron persei is about 1000-1500 light years away) we'd have to wait for the light to reach us to observe it.

It all boils down to an educated guess....the more massive the star is, the more likely it will blow itself up in the near future!

Answer 5

What we see in the sky is basically a re-run of what was in the sky millions and millions of years ago. Many of those stars have burned out, but since it takes so long for the light to reach earth from out in space, we're only just seeing them now.

Answer 6

they could be, and some probably are, but it isn't likely. we've got a pretty good idea of a star's life cycle, and by analyzing the kind of light a star puts out, we can figure out more or less how old it is. and since stars live for billions and billions of years, it's a pretty good bet that most of the ones we're seeing now are still around, barring some intergalactic disaster that could have destroyed them.

Answer 7

We do not know. Any stars' light may not reflect the reality of that point in space at the time the light reaches the earth.

Answer 8

They could well have gone out by now, and certainly some of them have. In fact, there is nothing to say that the sun didn't go out eight minutes ago, as that is how long its' light takes to reach us.

Answer 9

Most of them have gone i think. it probably takes a million years for the light to get here. Space does my head in

Answer 10

Yes, absolutely right! Looking into the night sky is looking into a time machine. That's why things like the Hubble Deep Field are so amazing, we can look back almost to Big Bang itself.
Amazing, init?