WONDER #73: Why Is Pluto No Longer a Planet?

Question 1 of 3

Which of the following rules defining what makes a planet were not made in 2006, according to this Wonder?

1. A planet must orbit the sun.
2. A planet must currently support life.
3. A planet must be round.
4. A planet must have "cleared the neighborhood" of its orbit.

Question 2 of 3

What rule of planethood has Pluto failed to accomplish?

1. A planet must orbit the sun.
2. A planet must have "cleared the neighborhood" of its orbit.
3. Both A and D.
4. A planet must be round.

Question 3 of 3

How many dwarf planets are mentioned in this Wonder?

1. 2
2. 3
3. 4
4. 5

Check your answers online at https://wonderopolis.org/wonder/Why-Is-Pluto-No-Longer-a-Planet.