Problem #1:
a) Calculate the distance to a star whose parallax is 0.012 arcseconds
(NOTE: 1 arcsecond = 1/3600th of a degree).
b) If this star has the same luminosity as the Sun, what is its intensity
(in W/m2) when viewed from the Earth?
a) Assuming that this K star is a Main Sequence star and that Main Sequence
K stars have a luminosity of 0.4 Lo, calculate the
distance to the star cluster.
b) Further observations shows that this particular K star is actually
a red giant star (i.e., it's not on the Main Sequence). Since
the luminosity of K giants is more like 100 Lo, what is the true distance
to this cluster?
a) How much energy would be produced in the sun?
Remember that a fusion process some of the mass of hydrogen is
converted into helim, and some is converted into energy.
Assume that the Sun is 80% hydrogen by mass.
c) How long would it take for the Sun to radiate this much energy at its current luminosity?