Solar System

A giant ball of gas that forms within a nebula and produces its own light and heat through nuclear fusion

• star

• planet

• comet

• astronomical unit

A celestial object that revolves around a planet

• star

• planet

• moon

• asteroid

The attractive force that shapes stars & planets into spheres and controls the motion of our solar system

• astronomical unit

• gravity

• nebula

• light year

An extremely large “space cloud” made of dust and gas where stars are “born”

• astronomical unit

• terrestrial

• comet

• nebula

A celestial object made of ice, dust, and rock with a very elongated elliptical orbit around the Sun

• moon

• planet

• comet

• star

A large spherical object that orbits a star but whose orbit is cluttered with other massive objects

• planet

• dwarf planet

• moon

• nebula

Rocky and Earth-like surface

• astronomical

• terrestrial

• nebula

• celestial

A non-spherical chunk of rock and/or metal of varying size/mass that orbits the Sun

• asteroid

• planet

• dwarf planet

• moon

A large celestial object that orbits a star, has a spherical shape, and has a clear orbital path

• moon

• planet

• dwarf planet

• asteroid

This theory explains how a giant cloud of dust & gas condenses around an area of high mass. As it condenses it begins to spin, flattening into a disc where planetessimals eventually form planets which orbit around a star at the center.

• Big Bang Theory

• Disc Theory

• Geocentric Theory

• Nebular Theory