List at least three qualities that make an astronomical object a ...

[fagboi]

List at least three qualities that make an astronomical object a good standard candle.
 
  What will be an ideal response?

Question 2

Valles Marineris is the most striking example of a(n)
 
  A) scarp.
  B) shield volcano.
  C) oceanic trench.
  D) impact crater.
  E) rift valley.

[BUTTHOL369]

Answer to Question 1

All standard candles must have some observable property that allows us to recognize the object as a member of the unique class. For example, Cepheids vary in brightness in a characteristic way, allowing us to distinguish them from other stars; white dwarf supernova have a unique light-curve that allows us to distinguish them from massive star supernova. The remaining answers will vary, but some additional key properties include little statistical scatter in brightness; high luminosity so that they can be seen at a great distance; and relative commonness so that they can be found in many objects.

Answer to Question 2

E

[fagboi]

Wow, this really help

[Sarahjh]

Thanks for the timely response, appreciate it