8th Grade Astronomy Unit Review

Which of the following terms is used to refer to a stage in the life cycle of a star?

• frequency
• nebula
• luminosity
• magnitude

True or False:  Planets, stars, and comets are all objects that orbit our Sun. 

• True
• False- only planets & comets can orbit the Sun
• False- only planets & stars can orbit the Sun
• False- planets are the only objects that orbit the Sun

A star's brightness is directly dependent on the star's what?

• The size of the star- the smallest stars are the brightest
• The size of the star- the biggest stars are the brightest
• Temperature of the star- the hottest stars are the brightest the star will be
• The age of the star- the youngest stars are the LEAST bright

True or False: Scientist can determine the size of a galaxy by the number of light years away from Earth it is.

• True- bc the more light years it would take to reach it, the bigger it is
• False- bc size is determined by measuring its diameter in light years

Which of the following is a TRUE statement:

• Our Sun is the center of our galaxy
• Our Sun is located on the very outside of our galaxy
• Our Sun is on one of the arms in our galaxy that is approximately 2/3 away from its center
• Our Sun is on one of the arms in our galaxy that is closer to its center

Ultraviolet, Infrared, & visible light are examples of __________ being emitted by our Sun.

• radiation
• gamma rays
• gravity

 Light years are most helpful to scientists when they are measuring what?

• The speed of light
• The distances between objects in space
• The life cycle of our Sun
• The speed of a planet's orbit around the Sun

True or False:  When scientists see visible light from a supernova, they can determine when it occurred by measuring its distance away from earth in light years. 

• True- its distance away in light years = how long ago it exploded
• False- its distance away in light years = how long it took to explode

Which of the following is true about nuclear fusion?

• Occurs at the center of stars & produces energy
• Occurs in the process of chemical reactions
• Results in the creation of black holes
• Occurs when 2 stars collide 

Determining a star's mass identifies the star's current what?

• position in the galaxy
• temperature
• life cycle
• gravitational pull