Telescopes and space missions

Grade 9 Science Worksheet - Challenge Me

Circle the best answer.

1. 1.

   Four plan cards, labeled A to D. Esme plans to study faint, cool dust clouds that glow in far infrared. Which plan fits?

   • A cooled infrared telescope in space
   • A small telescope flown closer to the clouds
   • A visible-light telescope on a mountain
   • A radio dish, since infrared is radio
2. 2.

   1 light-day ≈ 2.6 × 10¹⁰ km; 1 AU ≈ 1.5 × 10⁸ km. About how many AU is one light-day (about 2.6 × 10¹⁰ km), using 1 AU ≈ 1.5 × 10⁸ km, by Kira's math?

   • About 0.006 AU
   • About 173 AU
   • About 17,300 AU
   • About 1.7 AU
3. 3.

   Luz's friend says space telescopes are better because they are closer to the stars. Which response is best (NASA)?

   • Agree: each kilometer up helps a lot
   • Disagree: ground telescopes see each kind of light just as clearly
   • Agree: Hubble flies near the stars
   • Disagree: they gain by being above the air, not by being closer
4. 4.

   Two mirrors, one twice as wide, with areas shaded. Milo's cousin says doubling a mirror's width doubles the light it gathers. Which response is best?

   • Agree: light grows with width
   • Disagree: twice as wide gathers 4 times the light
   • Agree: and doubling again gives 3 times
   • Disagree: mirror size does not matter
5. 5.

   Noah's friend says Mission Control can steer a Mars rover live, like a video game. Which response is best?

   • Disagree: signals take minutes each way, so commands are planned
   • Agree: the delay is under a second
   • Disagree: rovers get no commands
   • Agree: radio reaches Mars at once
6. 6.

   Hubble, 2.4 m, orbiting Earth, about 560 km up; Webb, 6.5 m, orbiting the Sun, 1.5 million km from Earth. Compare Webb's distance from Earth (1.5 million km) with Hubble's height (about 560 km). About how many times farther is Webb, by Pia's math?

   • About 2,700 times
   • About the same distance
   • About 270,000 times
   • About 27 times
7. 7.

   Light gathered grows with diameter squared. A team wants images 4 times as bright from faint galaxies. By how much must the mirror's diameter grow, by Ren's math?

   • Twice the diameter
   • 4 times the diameter
   • 16 times the diameter
   • It cannot be done
8. 8.

   17 km/s; one year 3.16 × 10⁷ s. NASA gives Voyager 1's speed as about 17 km/s (61,000 km/h) relative to the Sun. About how far does it go in one year (3.16 × 10⁷ s), by Tala's math?

   • About 1 AU
   • About 5.4 × 10¹⁵ km, a light-year
   • About 17 km
   • About 540 million km, about 3.6 AU
9. 9.

   The spectrum with the air's open and blocked bands, plus ground and space telescopes. Why do astronomers use both ground and space telescopes, by Ari's reading?

   • Ground ones can be huge; space ones see the blocked light
   • Space ones are closer to the stars
   • Ground telescopes see each kind of light, so space adds little
   • Bigger mirrors matter just in space
10. 10.

    Voyager 1 launched in 1977 from Cape Canaveral, Florida, and is still sending data (NASA). Why does a one-light-day distance make every command a careful plan, by Bo's reading?

    • Each command takes a day to arrive, and the reply a day to return
    • Voyager is just a few hundred km away
    • Voyager is a rover on Mars
    • Commands arrive at once