How can astrophysicists tell whether a star is receding from or approaching earth?

Question

How can astrophysicists tell whether a star is receding from or approaching earth?

in progress 0
Thanh Hà 5 years 2021-08-20T12:35:24+00:00 1 Answers 21 views 0

Answers ( )

  1. Dau
    0
    2021-08-20T12:37:19+00:00
    Reply

    Answer:

    Doppler shift of the starlight

    Explanation:

    To predict the movement of a star, we compare the spectra of elements found in star (H, He Na etc.), first spectra which are obtained from star and second spectra from laboratory. If spectral lines of the spectra obtained from star, are shifting towards red end (called red shift) then star is going away from earth and if shifting is towards blue (called blue shift), then star is approaching the earth. This is Doppler’s shift.

Leave an answer

Browse

Giải phương trình 1 ẩn: x + 2 - 2(x + 1) = -x . Hỏi x = ? ( )