MedVision ad

Question! (1 Viewer)

Vall

Well-Known Member
Joined
May 9, 2021
Messages
303
Gender
Male
HSC
2022
I would almost say B? We can determine distance via the amount of redshift each galaxy's spectra undergoes (by Hubble's law the distance from us is directly proportional to recessional speed) so A and C are eliminated as they are the most redshifted (so furthest away). D is redshifted a bit and b doesn't seem to be Doppler shifted at all - which I don't know how to interpret.
 

wizzkids

Well-Known Member
Joined
Jul 13, 2016
Messages
330
Gender
Undisclosed
HSC
1998
The question is examining Hubble's relation between red-shift, velocity of recession and distance. This relation holds true for large distances, but within the local group, it is not true. There are galaxies like M31, the Andromeda galaxy and the Large Magellanic Cloud, which are part of our local group that are actually approaching us, so they show slight blue-shift. I think "B" is the correct answer, (unless the examiner is being misleading and Galaxy V is our Milky Way). Where was this question published?
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top