The Solar System MS-ESS1-3

Asteroid

A body of rock and metal that orbits the Sun. An asteroid is a small, rocky object that orbits the Sun, mostly found in the asteroid belt between Mars and Jupiter.

Astronomical unit

The average distance between Earth and the Sun, about 150 million km, or 93 million miles, is called an astronomical unit. An astronomical unit is a way to measure distances in space using the average distance from Earth to the Sun.

Comet

A body of ice, rock, and dust that orbits the Sun. Comet. A comet is a small space object made of ice and dust that travels around the Sun, often showing a bright tail when near the Sun.

Gas giant

a large planet made up mostly of gases, like Jupiter or Saturn. gas giant. A gas giant is a big planet that is mostly made of gases instead of solid rock.

Light year

The distance light travels in a year 9.5 trillion km. light year. A light year is the distance that light travels in one year.

Moon

A natural body that revolves around a planet is called a moon. Moons are objects that orbit planets and can vary in size and composition.

Scale

A ratio of the size of a model to the object it represents.. scale. Scale is how we compare the size of a smaller model to the real-life object it represents.

Terrestrial planet

One of the four rocky planets of the inner solar system, Mercury, Venus, Earth, or Mars, is a terrestrial planet. A terrestrial planet is a planet that is made mostly of rock and metal and has a solid surface.