Solar System Flashcards
Astronomical units (AU)
A unit of distance equal to the average distance between Earth and the sun, about 150 million kilometers.
Solar system
The system consisting of the sun and the planets and other objects that revolve around it.
Planet
Round, orbit the sun, and have cleared out the region of the solar system along its orbit. (This means it doesn’t share the area of its orbit with any other objects)
Dwarf planet
An object that orbits the the sun and has enough gravity to be spherical, but has not cleared the area of its orbit.(this means other objects also share its orbit)
Asteroid
Small, mostly Rocky bodies that orbit the sun
Comets
A loose collection of ice and dust that orbits the sun, typically in a long, narrow orbit.
Planetesimal
One of the small asteroid-like bodies that formed the building blocks of the planets.