Pluto: The Planet That Wasn't

Pluto used to be considered a planet. Today, what is it considered to be?
 

• It is considered to be a dwarf planet.
•  It is considered to be a star.
•  It is considered to be a comet.
• It is considered to be an asteroid.

How does the text describe Pluto?
 

• Pluto is made up entirely of ice, and it is bigger than Venus.
•  Pluto is made up entirely of rock and ice, and it is bigger than Earth's moon.
• Pluto is made up entirely of gas, and it is bigger than Earth's moon.
• Pluto is made up entirely of rock and ice, and it is smaller than Earth's moon.

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?

• because Pluto and Eris are both space objects
• because Pluto and Eris were discovered at the same time
• because Pluto and Eris are very different
• because Pluto and Eris are very similar

What is the main idea of this text?

• Pluto was no longer considered a planet after the discovery of Eris made scientists come up with new rules for what is counted as a planet.
• Pluto is so far away that it took the NASA New Horizons spacecraft over 11 years to get there from Earth.
• Eris is about the same size as Pluto, and like Pluto, it is part of a ring of objects that circle the outer edge of the solar system
• Scientists come up with rules for what is counted as a planet and what is not.

Choose the answer that best completes the sentence.

After scientists made new rules for what is counted as a planet, Pluto was no longer considered a planet. _________, the official list of planets in the solar system went from nine to eight.

• Therefore
• Although
• On the other hand
• Especially

"A new category was created: dwarf planet. The official list of planets in the solar system went from nine to eight, and Pluto and Eris became members of the dwarf planet club. So long for Planet Pluto—but at least it no longer has to be the littlest guy in the club. In fact, Pluto is the biggest of the dwarf planets! Maybe Pluto doesn’t have it so bad after all."

What does the author mean by stating, "Maybe Pluto doesn't have it so bad after all"?

• Even though Pluto is no longer counted as a planet, it is in a new group called dwarf planets.
• Even though Pluto is no longer counted as a planet, it is the biggest of the dwarf planets.
• Even though Pluto is no longer counted as a planet, it is still part of the ring of objects that circle the outer edge of the solar system.
• Even though Pluto is now counted as a dwarf planet, it isn't alone as other space objects are counted as dwarf planets.