3 Things I learned: 

1. I learned that most of the heavy elements in space are shown when a supernova happens
2. I learned SDSS is an optical telescope. And optical telescopes can tell how bright things really are
3. I learned that quasars are massive black holes in the center of a galaxy 

2 things I thought were amazing!! 
 1. The fact that in the beginning a star will mostly have light elements, then when it blows up, all the heavy elements will show up!
2. Also that SDSS provides a lot of research for many scientists. The creators never thought their work would be recognized as much 

1 question
1. I would like to ask Don York how can the youth use optical astronomy