Extra Problems - Stars

  1. A star has a parallax of 0.015 arc seconds. What is its distance in parsecs?
  2. A star radiates most strongly at 150 nm. Use Wien's Law to find its surface temperature.
  3. A binary star pair has an orbital period of 6 years. The stars are separated by 4 AU. What is their combined mass in Solar units?
  4. A star has a surface temperature of 24,000 K and a luminosity 10,000 times that of the Sun. What is the star's radius in solar units?
  5. Calculate the average density of a red giant star given that its mass is 2 solar masses and that its radius is 50 times that of the Sun. Take the Sun's mass to be 2x1033 grams and its radius to be 7x1010 cm.
  6. Two stars in orbit around each other complete their revolution in 20 years. They are 10 AU apart. What is their combined mass in solar units?