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Our Sun is orbiting the center of the Milky Way galaxy. So many years ago, it was at a different location from where it is now. In addition, we are observing stars and exoplanets as they were many years ago, for example stars like Sirius..

In this case, why can't we see our own Sun in its orbital path a few hundred years back. Is there any specific reason why we can't see/observe our Sun from the past?

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  • $\begingroup$ I made a few modifications. Feel free to edit it again if you think I left anything out. $\endgroup$
    – usernumber
    Commented Jan 16, 2020 at 10:56
  • $\begingroup$ We see it from its past, as it was about 8 minutes brfire. It is the same as for Sirius, just the distance and thus the time taken by its image to arrive is short. $\endgroup$
    – Alchimista
    Commented Jan 18, 2020 at 8:58

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Our Sun moves through the galaxy much slower than light does. So the light that was emitted last year by the Sun is already very far away from the Earth. Therefore, we don't receive any light from (i.e. we don't see) the Sun as is was last year.

As an analogy, image walking along and shooting bullets in all directions. The bullets are going much faster than you can go by walking, so you won't ever get hit by your own bullets. But someone walking next to you can get hit by the bullets you are shooting out.

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    $\begingroup$ Our speed doesn't really matter. Even if we did move close to the speed of light, light would still move at the speed of light wrt. us and our position. $\endgroup$
    – pela
    Commented Jan 16, 2020 at 13:40
  • $\begingroup$ Our exact speed doesn't matter, but the fact that we can't move faster than light does. In the analogy, if you walk faster in a circle than the bullets go in a straight line, the bullets could still catch up to you. $\endgroup$
    – usernumber
    Commented Jan 16, 2020 at 15:38
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    $\begingroup$ We see the Sun as it was about 8 minutes ago as that's the time taken for light to cover the roughly 147 million km. If we wanted to see the Sun further back in time, we would have to be further away as we are for the other stars $\endgroup$
    – astrosnapper
    Commented Jan 16, 2020 at 17:38
  • $\begingroup$ You just have to go further away before you start looking. $\endgroup$
    – tomc
    Commented Jan 18, 2020 at 4:57
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    $\begingroup$ How can this be upvoted? $\endgroup$
    – Alchimista
    Commented Jan 18, 2020 at 9:00

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