What made supernova 1987a so useful to study? A) We saw direct ...

[sjones]

What made supernova 1987a so useful to study?
 
  A) We saw direct evidence of nickel to iron decay in its light curve.
  B) Its progenitor had been observed previously.
  C) In the Large Magellanic Cloud, we already knew its distance.
  D) It occurred after new telescopes, such as Hubble, could observe it very closely.
  E) All of the above are correct.

Question 2

Of all visible objects in the celestial sphere, which appears to move the least? Why?
 
  What will be an ideal response?

[Eazy416]

Answer to Question 1

E

Answer to Question 2

Polaris, because it lies very close to the north celestial pole, making everything else seem to revolve around it as the Earth rotates on its axis daily.