1. What are the causes of reflection nebulae? What are the essential ingredients (what kinds of astronomical objects) that enable us to see these objects?

2. Find images on the Internet of a "dark nebulae," "reflection nebulae," and "emission nebulae." Pick one example of each category, describe the image.

3. Describe how the ultra-cold material in the interstellar medium eventually gets hot enough to cause hydrogen at the center of the protostar to begin to fuse to helium.

4. Use the Internet to track down information on M11 (The Wild Duck Cluster).

a.  What kind of object is M11, and where is it in the Universe?
b.  Where is M11 in the sky and what time of year is it observable?
c.  How far from Earth is M11, and how old is it?