When is a Planet Not a Planet? Comprehension Quiz

Most scientists think the world began as a ​ (a)   .

• nebula
• star
• comet
• planet

Tags

CCSS.RI.2.1

CCSS.RI.3.1

CCSS.RL.1.1

CCSS.RL.2.1

CCSS.RL.3.1

What is the main difference between the planets in our solar system?

• The planets closes to the sun have a rocky surface and the planets farthest from the sun are made up mostly of gas.

• The planets farthest from the sun have a rocky surface and the planets closest to the sun are made up mostly of gas.

• The planets closest to the sun travel outside their own orbits, but the planets farthest from the sun have their own orbits.

• The planets farthest from the sun travel outside their own orbits, but the planets closest to the sun have their own orbits.

What finding made astronomers begin to doubt Pluto was a planet

• They discovered that it traveled around the Sun in an oval-shaped orbit.

• They found that although it was the farthest planet from the Sun, it had a rocky surface.

• They discovered that it had enough gravity to "clear the neighborhood" around its orbit.

• They found that although it was the farthest planet from the Sun, it was made up mostly of gas.

According to the selection, what do the Planet Finders use to look for planets?

• a camera and a computer

• the Hubble Space Telescope

• a wide-field telescope and a camera

• the Hubble Space Telescope and a camera

Tags

CCSS.RI.4.2

CCSS.RI.5.2

CCSS.RI.6.2

CCSS.RL.5.2

CCSS.RL.6.2

Ad defined by the IAU, what category of celestial bodies orbits the Sun, is round, and is not a moon or satellite of another planet?

• asteroids

• comets

• dwarf planets

• planets