Planets and other objects in the solar system

Grade 6 Science Worksheet - Challenge Me

Circle the best answer.

1. Read this first

   Use this

   Data table (NASA Planetary Fact Sheet, 2025), columns Planet, Diameter (km), Moons and Rings. Mercury: 4,879, 0, no. Earth: 12,756, 1, no. Mars: 6,792, 2, no. Jupiter: 142,984, 95, yes. Saturn: 120,536, 274, yes. Neptune: 49,528, 16, yes.

2. 1.

   The table shows small rocky planets close to the Sun and giants farther out. Which explanation fits NASA's account, Bo?

   • Near the young Sun, only rock could stand the heat
   • The inner planets are moons of the Sun, so they stay small
   • The inner planets lost their rings to the Sun
   • The giants were rocky once and then swelled up
3. 2.

   Astronomers find a planet around another star: about 120,000 km wide, with rings and many moons. Using the table, which planets is it most like, Esme?

   • The dwarf planets, like Pluto
   • The giant planets, like Saturn
   • The asteroids, like Vesta
   • The rocky planets, like Earth and Mars
4. 3.

   Mystery card: icy, a few kilometers across, grows a glowing cloud and a tail as it nears the Sun. What is it, and where might it come from, Jun?

   • A meteorite, from Earth's ground
   • An asteroid, from the main belt between Mars and Jupiter
   • A comet, from the Kuiper Belt or the Oort Cloud
   • A dwarf planet, from inside Mars's orbit
5. 4.

   Mystery card: round, orbits the Sun in the Kuiper Belt among many icy bodies, and has five moons. What is it, Kira?

   • Pluto, the ninth planet
   • Ceres, in the asteroid belt
   • Charon, a moon
   • Pluto, a dwarf planet
6. 5.

   Mystery card: a pebble-sized rock found in a field after a bright streak crossed the sky. Before it reached Earth's air, what was it called, Luz?

   • A meteorite
   • A meteor
   • A meteoroid
   • A comet's tail

7. Use this

   Orbit diagram from above, not to scale:

9. 6.

   Milo follows the comet in the diagram. At which position does it have its biggest glowing cloud and tail?

   • Q, near Jupiter's orbit
   • The same at P, Q and R
   • R, closest to the Sun
   • P, farthest from the Sun
10. 7.

    At position R, which way does the comet's tail point, Noah?

    Use the picture in question 6.

    • Away from the Sun
    • Toward the Sun
    • Straight toward Earth
    • Toward Jupiter
11. 8.

    The comet has no tail at P but a long one at R. Which explanation, with its reason, fits, Pia?

    Use the picture in question 6.

    • Heat: near the Sun, its ices turn to gas that is pushed away
    • Rock: it scrapes against the asteroid belt and sheds dust
    • Gravity: Jupiter stretches it into a tail
    • Air: it glows in Earth's air like a meteor
12. 9.

    Ren's friend says Pluto is a planet because it is round and orbits the Sun. Which response is best?

    • Disagree: it hasn't cleared its orbit, so it is a dwarf planet
    • Disagree: Pluto is a moon of Neptune
    • Agree: round things that orbit the Sun are planets
    • Agree: it has five moons, so it is a planet
13. 10.

    Zee's cousin says a shooting star is a real star falling to Earth. Which response fits?

    • Disagree: it is a comet crashing into the Moon
    • Agree: old stars fall out of the sky
    • Disagree: it is a meteor, a space rock glowing in our air
    • Disagree: it is a meteorite still out in space