Ok, so I have read about how exoplanets are found using all sorts of genius methods. I also understand the further an obect in a telescope is the further into the past I am looking.

So given that we are finding exoplantets with methods that go well beyond any practical visual range are we fnding these exoplanets 'in their past' as well? As far as I understand radio telescopes and other methods can't travel faster than light therfore their results are also from past events, is my reasoning in this right?

  • $\begingroup$ Yes, you are correct. We see the stars as they looked years ago (based on how many light years distant they are). So the exoplanets we detect are also as they were years ago. As you point out, information can't travel faster than light. $\endgroup$
    – user21
    May 20 '15 at 3:50
  • $\begingroup$ Ok so I was reading about the fermi paradox, assuming life will form and thrive where possible, then there is a probable chance many other earths formed, son lets say we find a planet with life on it with radio technology in our frame of reference ,but it is say 5000 light years away we would never pick up the signal so maybe the reason we haven't seen signs of advanced life is because of this realitivistic time bubble? $\endgroup$ May 20 '15 at 3:56
  • $\begingroup$ Sorry for any spelling issues, i am writing from my phone. $\endgroup$ May 20 '15 at 4:02
  • $\begingroup$ Posting new question based on comment. $\endgroup$ May 20 '15 at 4:06

Yes, you are indeed correct. We always see what was happening at a given location when the light was emitted there for us to be detected. Let's assume we observe a oscillating star 100 light years away by measuring the shift in frequency of the detected light. That means that the star was actually oscillating a hundred years earlier and we just happen to observe it now; But we (that means nobody) have no way of knowing what is happening now due to the fact that information can't travel faster than light (especially when the information is transmitted via light as in our case).


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