Previewing Questions

LIVE FROM THE EDGE OF SPACE AND TIME Pre-viewing Questions
Tuesday April 3, 2001 (13:00 Eastern)

1) How many "sheets of paper" is it to Pluto?

Answer: (40, if the Earth-Sun distance is scaled to the thickness of one sheet of paper.) How many sheets of paper to the edge of the Universe? (50 million kms, 31 million miles worth!)

2) What color are the hottest stars?

Answer: (Blue.)

3) How far back can Chandra see?

Answer: (so far, about 12 billion years.)

4) What does Chandra see at that distance?

Answer: (Supermassive black holes at the center of galaxies.)

5) How does Andrea Ghez detect a black hole at the center of the Milky Way?

Answer: (Through the speedy orbital motions of stars.)

6) Does light moving away from you become "redder" or "bluer"?

Answer: (Redder)

7) Do you hear or see the Doppler Shift?

Answer: (You can do both.)

8) Arrange in descending size order: atoms, quarks, protons and neutrons.

Answer: (Atoms, protons and neutrons, quarks.)

9) What did Edwin Hubble discover about galaxies?

Answer: (That they were receding from each other, the farther ones the fastest.)

10) What do astronomers call the stuff that shapes clusters of galaxies, though we can't see it in visible light?

Answer: (Dark matter.)