Question

After Eris was discovered, scientists had to decide whether to count it as a planet. Why did this make them question whether Pluto should still be counted as a planet?
a
because Pluto and Eris are both space objects
b
because Pluto and Eris were discovered at the same time
c
because Pluto and Eris are very different
d
because Pluto and Eris are very similar

Answer 1

Answer:

After Eris was discovered, they had to decide whether Eris was a planet or not. If they decided it wasn't a planet, they had to also decide whether Pluto should be counted as a planet since Eris and Pluto were quite similar. They were the same size, and they were both part of the Kuiper Belt.

Explanation: