Which is true of Pluto?
A. Pluto revolves around the sun but does not rotate.
B. Pluto does not revolve around the sun.
C. Pluto is not always the planet farthest from the sun.
D. Pluto’s orbit is almost perfectly round.
The Correct Answer and Explanation is :
The correct answer is C. Pluto is not always the planet farthest from the sun.
Explanation:
Pluto is classified as a dwarf planet in the Solar System, and it has several unique characteristics compared to the eight major planets. Let’s examine each option:
A. Pluto revolves around the sun but does not rotate
This statement is false. Pluto does indeed rotate on its axis. In fact, its day is about 6.4 Earth days long. While Pluto’s rotation is very slow, it still completes a full rotation, similar to other celestial bodies.
B. Pluto does not revolve around the sun
This statement is also false. Pluto does revolve around the Sun, just like the other planets and dwarf planets in our Solar System. Its orbit, however, is much more elongated and tilted compared to the planets’ orbits.
C. Pluto is not always the planet farthest from the sun
This statement is true. Pluto’s orbit is highly elliptical (elongated), meaning that sometimes its orbit brings it closer to the Sun than Neptune. The two objects’ orbits are locked in a gravitational resonance, meaning that even though their orbits cross, they never collide. This arrangement keeps Pluto from being too close to Neptune. For about 20 years of its 248-year orbital period, Pluto is closer to the Sun than Neptune. However, it is still considered the farthest dwarf planet from the Sun.
D. Pluto’s orbit is almost perfectly round
This is false. Pluto’s orbit is not circular; it is highly elliptical. It has an eccentricity (a measure of how much an orbit deviates from being circular) of about 0.25, which is much more elongated than the near-circular orbits of the planets.
In summary, Pluto’s orbit is irregular, and due to its elliptical shape, it is not always the farthest from the Sun, making option C the correct answer.