Question

The star Polaris has an apparent magnitude of 1.98 and is located 133 parsecs away. What is Polaris's absolute magnitude? Express your answer to 3 significant figures. absolute magnitude:

Answer 1

usei distance 1 in pances Apparent magnifuole - Absolute magni hece = 5x lograres - 5 Pute vakers (133) 1.98 – Absolute magnihede = 5xlog! -5 1.98 - 5.6192 - Absolute magnitude. Abschte magnitude = -3.639

Answer 2

SOLUTION :

Distance of a star based on difference of apparent magnitude and absolute magnitude can be calculate by using the following formula :

Distance = 10 ^[ ((apparent magnitude - absolute magnitude) + 5) / 5 ]

=> 133 parsecs  =  10^[ ((1.98 - absolue magnitude) + 5) / 5 ]

=> 133 = 10^(6.98/5 - absolute magnitude / 5) )

Taking log :

log(133) = 6.98/5 - absolute magnitude / 5

=> absolute magnitude = 5 ( 6.98/5 - log(133)) 

=> absolute magnitude = - 3.639 (ANSWER).