Our Solar System

Asteroid

A body of rock and metal that orbits the Sun. An asteroid is a small, rocky object that travels around the Sun, mostly found 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 standard measurement used by scientists to describe distances in space.

Axis

The imaginary line around which Earth rotates, it runs through Earth from pole to pole. Axis. In simple terms, an axis is the line around which an object rotates.

Comet

A body of ice, rock, and dust that orbits the Sun. Comet. A comet is a small celestial body that travels around the Sun, leaving a bright trail of gas and dust as it heats up.

Constellation

a pattern or shape formed by a group of stars. constellation. A constellation is a recognizable pattern of stars in the night sky, often named after mythological figures or animals.

Corona

The outermost layer of the Suns atmosphere. Corona. It is the Sun's outer atmosphere that is visible during a solar eclipse.

Eclipse

An event where one object in space passes through the shadow of another object. An eclipse is when one celestial body moves into the shadow of another, blocking sunlight.

Equinox

The two days a year when the Sun is directly over the equator, making day and night equal. Equinox. An equinox is when the length of day and night are nearly the same because the Sun is directly above the equator.

Galaxy

A massive system of stars, gases, and dust held together by gravity. Galaxy. A galaxy is a huge collection of stars, planets, and other matter bound together by gravity.

Gas giant

a large planet made up mostly of gases, like Jupiter or Saturn. gas giant. A gas giant is a massive planet primarily composed of hydrogen and helium.

Meteor

A streak of light created when a meteoroid is heated by Earths atmosphere. Meteor. A meteor is a bright trail of light in the sky caused by a space rock burning up as it enters Earth's atmosphere.

Meteorite

A meteoroid that lands on the surface of Earth, a moon, or a planet. Meteorite. A meteorite is a rock from space that survives its fiery journey through the atmosphere to reach a planet's surface.

Moon phase

Changes in the shape of the moon as seen from Earth. Moon phase. A moon phase is the different shapes of the moon we see from Earth as it orbits around us.

Orbit

The path of one body around another, like Earths orbit around the Sun. Orbit. In science, an orbit is the curved path that an object takes around a star, planet, or moon due to gravitational forces.

Penumbra

A region of lighter shadow around the darkest part of a shadow. Penumbra. In Science, a penumbra is the lighter part of a shadow where some light still reaches, surrounding the darkest part called the umbra.

Revolution

The motion of one body around another, like the Earth around the Sun. Revolution. In Science, revolution is the complete orbit one object makes around another, such as a planet around a star.

Solar system

A group of planets and other objects that revolve around a sun. Solar system. The solar system is a collection of planets and celestial bodies orbiting around a central star, the Sun.

Solstice

The twice yearly event when the Sun reaches its greatest distance North or South of the equator. Solstice is when the Earth's tilt makes the Sun appear at its highest or lowest point in the sky.

Sunspot

A spot on the Sun which appears darker because it is not as hot as other areas. Sunspot. Sunspots are cooler regions on the Sun's surface caused by magnetic activity, leading to their darker appearance.

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 made mostly of rock and metal with a solid surface.

Umbra

The darkest part of a shadow. Umbra. The umbra is the fully shaded, darkest section of a shadow, where the light source is completely blocked.

Universe

Everything that exists, including the stars, planets, and energy. universe. The universe is all of space and everything within it, like planets, stars, and galaxies.