Question

What three criteria must an object fulfill to be considered a planet?

Options:
a) Orbiting the Sun, Spherical Shape, Clearing Orbit Path
b) Having Moons, Regular Shape, Close to Earth
c) Presence of Rings, Massive Size, Solar Alignment
d) Highly Reflective Surface, Elliptical Orbit, Unique Composition

Answer 1

An object must orbit the Sun, have sufficient mass to assume a spherical shape, and clear its orbital path to be considered a planet. Those meeting only the first two criteria, like Pluto, are classified as dwarf planets.

Step-by-step explanation:

For an object to be considered a planet, it must meet three specific criteria set by the astronomical community. These criteria are:

1. The object must be in orbit around the Sun.
2. It must have a sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape.
3. The object must have cleared the neighborhood around its orbit, meaning it is gravitationally dominant and there are no other bodies of comparable size other than its own satellites or those otherwise under its gravitational influence.

A body that meets only the first two criteria is classified as a dwarf planet. A famous example of this is Pluto, which was demoted from planet status in 2006 when the definition of a planet was revised.