Solar System

Why is Pluto no longer a planet and how big is our solar system?

An engaging journey through the solar system to understand the true scale of our neighborhood and why Pluto was reclassified as a dwarf planet.

Check your understanding

1. What holds our solar system together at the center?
- A. The Moon's brightness
- B. The Sun's gravity
- C. A ring of asteroids
- D. The Earth's magnetic field
2. Why is Pluto now classified as a dwarf planet?
- A. It is too cold
- B. It moved to a different galaxy
- C. It has not cleared its orbital path of other objects
- D. It is larger than Jupiter
3. Which group of planets is known for being small and rocky?
- A. Mercury, Venus, Earth, and Mars
- B. Jupiter, Saturn, Uranus, and Neptune
- C. The Kuiper Belt objects
- D. The Oort Cloud comets
4. What is the name of the cloud of gas and dust from which the Sun formed?
- A. A black hole
- B. A constellation
- C. A nebula
- D. A solar flare

1. If the Sun’s gravity disappeared, what would happen to the planets?
- A. They would crash into each other
- B. They would drift off into space in a straight line
- C. They would become stars
- D. They would stop spinning instantly
2. Why is Venus hotter than Mercury, even though it is farther from the Sun?
- A. It has a runaway greenhouse effect from thick clouds
- B. It is closer to the Asteroid Belt
- C. It produces its own light like a star
- D. It reflects more solar wind
3. What is the main reason Earth is protected from the damaging solar wind?
- A. The Asteroid Belt acts as a shield
- B. Earth is too small to be hit
- C. The Moon reflects the solar wind
- D. Earth has a strong magnetic field
4. Why would it be impossible to 'jump' from planet to planet?
- A. Planets are only made of gas
- B. The planets are millions of miles apart
- C. Gravity makes jumping impossible in space
- D. The planets move too fast to see

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