Question 1:
Discuss how new detectors that allow us to see more of the electromagnetic spectrum (outside of visible light) have opened up new astronomical knowledge. NOTE AGAIN: this answer should discuss electromagnetic radiation that is NOT visible light.
Question 2:
At one time, it was believed impossible to determine what stars were made of. Spectroscopes, together with on-earth experiments have made this possible. Is there anything else that we think currently impossible to determine that we might be able to measure in the future?
Question 3:
There are other ways than electromagnetic radiation to "see" other parts of the universe. I have discussed neutrinos and gravitational waves in the lecture; cosmic rays and meteorites give us actual samples of extraterrestrial material. Discuss what one of these sources other than electromagnetic radiation can tell us that light cannot.
Question 4:
We now know that most of the material in the Earth and in our bodies was created in ancient stars. Discuss how this affects our viewpoint about our place in the universe. Consider how this might have affected people years ago, when the heliocentric model was still not universally accepted.