Unformatted text preview: 6. How can we determine the Milky Way’s diameter? By using parallax with nearby stars. 7. How can we determine the Milky Way’s mass? By the gravitational attraction needed to hold the stars in orbit 8. What is meant by dark matter? Why do astronomers conclude the Milky Way may contain such as yet unobserved material? Unseen matter that emits no radiation. When they do the mass math of visible stars and gas it only adds up to 1/10 of the mass needed to hold our galaxy together 9. What is the evidence for a black hole at the center of the Milky Way? We can see the event horizon where things appear to swirl around it then only blackness after that. 10. What is meant by a Pop III star? They are hypothetical ancient pure hydrogen and helium stars....
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This note was uploaded on 02/12/2010 for the course GEOS 210 taught by Professor Mr.schubert during the Spring '09 term at Butler CCC.
- Spring '09