How to determine distances by using apparent and absolute magnitudes?

Question

Good day everyone,

After approximately 7 hours from now I have a final exam on Astronomy class and I`m confusing about how to determine distance by using apparent and absolute magnitudes?
Could you please explain that for me plus the meaning of both M and m by a basic explanation?

Thank you very much I really appreciate what you will offer of help to me.

Answer 1

The little m stands for apparent magnitude and is what the celestial object looks like in out night sky. The big M stands for absolute magnitude and is how bright it actually is at 10 parsecs. Now if an object has an apparent magnitude of -1 and an absolute magnitude of +8 you know that it gets dimmer if you are moving it to ten parsecs. Therefore it must be closer than a star that has a m of -1 and a M +4 because star 1 gets dimmer by 9 levels however star 2 only gets dimmer by 5 levels. This also works for stars getting brighter as you move it to 10 parsecs.

Answer 2

Since

m - M = 5[log(d_pc) -1],

log(d_pc) = 1+[(m - M)/5],

d_pc = 10ⁿ {10 to the power of n}

where n = 1+[(m - M)/5].

This distance is in paresecs (that is why 'pc' is used), which when multiplied by 3.26161 gives in Light Years.

Apparent magnitude is what the Star appears to be on Earth (here).

Absolute magnitudes is imagined magnitude viewed when the star is imagined at a distance of 10 pc (instead of what its actual distance is).

Answer 3

c), with ONE considered necessary element. This assumes that the two stars are of an analogous spectral style. The importance scales are counter-intuitive. A importance 6 huge call is fainter than a importance a million or importance 0. The sunlight's obvious importance is -26. an analogous is actual for truly the importance scale. At a distance of 10 parsecs, 32.6 gentle years, the plain and absolute magnitudes of stars would be an analogous.