Telescopes and space missions

Grade 9 Science Worksheet

Circle the best answer.

1. 1.

   Hubble, 2.4 m, orbiting Earth, about 560 km up; Webb, 6.5 m, orbiting the Sun, 1.5 million km from Earth. Light-gathering area grows with mirror diameter squared. About how many times more area does Webb's 6.5 m mirror have than Hubble's 2.4 m, by Bo's math?

   • About 20 times
   • About 7 times
   • About 2.7 times
   • About 4.1 times
2. 2.

   A 10 m mirror is compared with a 2.5 m mirror. How many times more light does it collect, by Jun's math?

   • 4 times
   • 16 times
   • 7.5 times
   • 64 times
3. 3.

   Time = distance ÷ 300,000 km/s; distance 225 million km. Mars is 225 million km from Earth on a given day. About how long does a radio command take to reach a rover there, at 300,000 km/s, by Kira's math?

   • About 0.75 s
   • No time
   • About 12.5 hours
   • About 12.5 minutes
4. 4.

   One-way signal time 12.5 minutes. A command takes 12.5 minutes to reach that rover. How long before the team can see the rover's reply, by Luz's math?

   • About 25 minutes
   • At once
   • About 12.5 minutes
   • About 6 minutes
5. 5.

   Light speed 299,792 km/s; one day 86,400 s. A light-day is 299,792 km/s × 86,400 s. About how many kilometers is that, by Milo's math?

   • About 26 million km
   • About 26 billion km
   • About 26 trillion km
   • About 300,000 km

6. Read this first

   Use this

   Four telescope cards, labeled A to D.

7. 6.

   Noah wants to study X-rays from a hot gas cloud. Which telescope fits?

   • A larger visible-light mirror on the ground
   • An X-ray telescope in space
   • A radio dish on the ground
   • An X-ray telescope on a mountaintop
8. 7.

   Pia wants to map radio waves from a distant galaxy. Which telescope fits?

   • A radio dish on the ground
   • A telescope sent close to the galaxy
   • A radio telescope that must be in space
   • A gamma-ray telescope
9. 8.

   Webb at L2 with its sunshield facing the Sun, Earth and Moon. Webb studies mostly infrared light. Why does it fly far from Earth, behind a sunshield, by Ren's reading (NASA)?

   • Because infrared passes easily through the air
   • To stay near Earth's warm surface
   • To get closer to distant galaxies
   • To stay cold enough to sense faint infrared
10. 9.

    New Horizons launched on Jan. 19, 2006 and flew past Pluto on July 14, 2015 (NASA). About how long was the trip, by Tala's math?

    • About 6 years
    • About 9.5 years
    • About 15 years
    • About 2 years
11. 10.

    NASA's Perseverance launched July 30, 2020 and landed Feb. 18, 2021. About how many months was the trip, by Zee's math?

    • About 6.5 months
    • About 18 months
    • About 2 months
    • It did not land; it is an orbiter