Week 5 Discussion Questions (1 point each, total of 4 points)

1. Describe as accurately as you can what kind of stellar evolution process(es) is responsible for most of the iron in your blood (and anywhere else in the universe).
2. Suppose you take a picture of a certain star-field as a reference. Now, imagine a black hole comes between you and the center of the same star-field, and the black hole is relatively near to you. Describe how the appearance of the star-field might change. (Hint - one of the APOD images contains the clue).
   http://antwrp.gsfc.nasa.gov/apod/ap001210.html
3. Newton’s law of gravity describes the force between the Sun and Earth that keeps the two bodies in orbit around each other. (Since the Sun is so much more massive than Earth, Earth does most of the moving and we say it orbits the Sun). If the Sun were instantly to become a black hole (with mass = 1 SolarMass), would Earth's orbit change? Explain your answer.
4. The search for black holes has so far turned up some fairly convincing stellar-sized candidates in binary star systems. What observations could you make to distinguish whether the unseen object in one of these systems is a black hole or a neutron star?