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Astronomy Questions about Black Holes and Cluster Age (HR Diagrams)?
1. When observing the orbits of stars around a black hole, what properties of the orbits do you need to determine to calculate the mass of the black hole? What are sources of uncertainty in this calculation?
2. How do we determine cluster ages based on the star's location on the HR diagram? What constraints are placed on the age by observing a single main sequence star in the cluster?
Thanks a lot!
2 Answers
- digquicklyLv 77 years agoFavorite Answer
Well, ..., you can easily answer these two homework questions with a simple web search. Please go to the links below and read the materiel there. You will gain much knowledge from them.
http://en.wikipedia.org/wiki/Black_hole
- 7 years ago
The first is straightforward. The mass of any system is determined by both the speed of the orbit and the distance of the star (or planet in other cases). The more distant a body, the slower it orbits. For any given distance, more massive bodies will orbit around their common center of mass faster than less massive bodies will.
With the second question we can say that the cluster could be older, but no younger than the age of the main sequence star (or at least the youngest m-s star in the cluster).
