What is a major difference in the composition of elliptical and spiral galaxies?

• Elliptical galaxies have almost no gas or dust between stars
• Elliptical galaxies vary more in shape than spiral galaxies
• Spiral galaxies have almost no gas or dust between stars
• Spiral galaxies only contain old stars

A supernova is the explosion of a dying:

• medium-mass star
• high-mass star
• protostar
• low-mass star

According to Hubble's law, the farther away a galaxy is:

• the faster it is moving toward us
• the slower it is moving toward us
• the slower it is moving away from us
• the faster it is moving away from us

What type of star is the Sun?

• Red giant
• White dwarf
• Red supergiant
• Main sequence

The HR diagram classifies stars based on their surface temperature and their:

• color
• diameter
• distance from Earth
• absolute brightness

What determines if a star becomes a white dwarf, neutron star, or a black hole?

• Its age
• Its mass
• Its brightness
• Its temperature

What color are the coolest stars?

• blue-white
• yellow
• orange
• red

The Milky Way is what type of galaxy?

• Spiral
• Elliptical
• Irregular

What is the distance between wave crests?

• Speed
• Amplitude
• Wavelength
• Frequency

What is a light-year?

• distance between two stars
• distance light travels in one year
• the time it takes light to travel 300,000,000 meters
• the time it takes light to travel to Earth from the Sun