2
Homework #5
•1. Mass
of the Binary stars: 1.8 solar masses
•2.
Parsecs & Parallax: d = 1/p, so 1/12 of an arcsec
•3. Most of the nearby stars are cool K and M
stars.
•4.
m=-1.5, M=1.4. Recall 10 pc is
about 30 lt. yrs.
–Hard
method: m – M = -5 + 5log(d/1pc), so less than 30 years
•5. d
=145 pc, M = -5.2, so m = 0.6 (other answers bad)
•6. Same
M, one star is type G, one is type B.
G is bigger.
