Measuring Distance

A light-year (ly) is the distance that light travels in one year. If a star is 3 ly from Earth, how long does it take light from that star to reach Earth?

• 3 min

• 3 hours

• 3 years

• 3 months

Astronomers use the light-year to describe the relationship between objects in space. For example, the Andromeda galaxy is 2.5 million ly from Earth. Which of the following units is most similar to the light-year?

• gram

• second

• kilometer

• degrees Celsius

Why do we use light years and astronomical units to measure distances in space?

• Scientists want to sound smart.

• Hubble discovered these units and wanted to use them.

• Space is too small to use km, it wouldn't make sense.

• Space is too big, vast, enormous to use traditional units, like miles.

_____________ is the average distance between the Earth and the Sun. It is denoted by _____

• Miles, 'Mi'

• Light Year, 'Ly'

• Astronomical unit, 'Au'

• Parsec, 'Pc'

Tags

NGSS.MS-ESS1-1

NGSS.MS-ESS1-3

Which are the special units used to measure the distances between heavenly or celestial bodies, like stars and planets?

• Astronomical Units

• Miles

• Kilometres

• Light Years

• Metres

au = __________.

• 1.469 x 10⁸ km

• 1.496 x 10⁸ km

• 1.964 x 10⁸ km

• 1.496 x 10^{7 km}

Tags

NGSS.MS-ESS1-3

The average distance between the Sun and Jupiter is _____.

• 5.2 au

• 4.3 au

• 5.2 ly

• 52 au

Tags

NGSS.MS-ESS1-2

NGSS.MS-ESS1-3

What is the primary unit used to measure astronomical distances within our solar system?

• Light-year

• Kilometer

• Astronomical Unit

• Parsec

If a spacecraft travels at a speed of 20,000 kilometers per hour, how long will it take to travel 1 Astronomical Unit?

• About 8 hours

• About 8 days

• About 8 weeks

• About 8 months

Which instrument is commonly used to measure short distances with high precision in a laboratory setting?

• Ruler

• Vernier Caliper

• Tape Measure

• Odometer