General Astronomy -
Spring 2014
Homework #11 - due April 21
1. (3 pt) When the Universe was 0.1 seconds
old, there were no 4He nulcei. Explain why.
2. (3 pt) How were the photons in the cosmic microwave
background produced?
3. (4 pt) There is a sphere with a diameter of 500 pc located
1 Gpc from Earth. You measure the angular size of the sphere
to be 0.15 arcseconds. What does that imply about the
geometry of the Universe?
4. (3 pt) How can dark energy be distinguished from normal
matter and energy?