WONDER #2087: Could Our Solar System Have a Ninth Planet?

Question 1 of 3

Scientists believe a potential ninth planet might be how many times as massive as Earth?

1. 2
2. 5
3. 10
4. 50

Question 2 of 3

Scientists believe a potential ninth planet could take how many years to make one trip around the Sun?

1. 5
2. 500
3. 1,555
4. 20,000

Question 3 of 3

Scientists believe a potential ninth planet may exist because of peculiar orbits they’ve witnessed in which objects?

1. nearby stars
2. Neptune
3. Kuiper Belt Objects
4. faraway galaxies

Check your answers online at https://www.wonderopolis.org/wonder/could-our-solar-system-have-a-ninth-planet.