Understanding Light Years

What is a light year?

• A light year is a measure of time.

• A light year is a unit of distance equal to the distance light travels in one year.

• A light year is a unit of weight used in astronomy.

• A light year is the speed of light in a vacuum.

How many kilometers are in one light year?

• 9460730472580.8 kilometers

• 1000000000000 kilometers

• 15000000000000 kilometers

• 5000000000000 kilometers

If a star is 4 light years away, how many kilometers is that?

• 37682520000

• 30000000000

• 50000000000

• 25000000000

What is the speed of light in kilometers per second?

• 150000

• 300000

• 299000

• 299792.458

How long does it take for light from the Sun to reach Earth?

• 15 minutes and 45 seconds

• 10 minutes and 15 seconds

• 5 minutes and 30 seconds

• 8 minutes and 20 seconds

If a galaxy is 10 million light years away, how far is that in kilometers?

• 100 million kilometers

• 4.2 billion kilometers

• 94610000000000 kilometers

• 500 million kilometers

What unit of measurement is used to express astronomical distances?

• Parsec

• Light-year

• Kilometer

• Astronomical Unit

How do you calculate the distance in light years from a given distance in kilometers?

• Distance in light years = Distance in kilometers + 9.461 x 10^12

• Distance in light years = Distance in kilometers - 9.461 x 10^12

• Distance in light years = Distance in kilometers x 9.461 x 10^12

• Distance in light years = Distance in kilometers / 9.461 x 10^12

If a spaceship travels at 10% the speed of light, how long would it take to reach a star 5 light years away?

• 50 years

• 10 years

• 25 years

• 100 years

What is the nearest star system to Earth in light years?

• 2.5 light years

• 10 light years

• 4.37 light years

• 1.2 light years