Why are star clusters almost ideal laboratories for stellar studies?
A) All stars in the cluster are the same size and luminosity.
B) Their combined light makes them much easier to spot from a distance.
C) Stars in clusters have the same age, similar composition, and are at the same distance away.
D) Stars in clusters are all relatively young and therefore shine brightly.
E) Like our Sun, stars in clusters are always located in the plane of the Milky Way Galaxy.
Question 2
While observing the Sun, you note a large number of sunspots. What can you conclude?
A) The Sun is less luminous than usual.
B) This is a period of low solar activity.
C) Earth's climate will be unusually cold.
D) The Sun's rotation is slower than average.
E) There are likely to be an above average number of flares and prominences.
The Types of Stars and Their Sizes
A Binary Star System
Spectral Line Motion in Binary Star Systems
Stars and the Interstellar Medium
Plotting the Ages of Stars
The Structure of an Old High-Mass Star