Asteroid
Rocks floating around in outer space
Atmosphere
The gasses held by gravity around Earth and around other planets
Constellation
A group of stars in the sky. They're often named after an animal, object, or person
Galaxy
A collection of thousands to billions of stars held together by gravity. The galaxy we live in is called the Milky Way.
Satellite
An object that orbits another object. A moon is actually a satellite. We also say satellite to refer to spacecraft people build that orbit Earth, other planets,
Dwarf Planet
Objects that are round and orbit the sun, just like planets do. But unlike planets, dwarf planets are not able to clear their path around the sun.
Gravity
A force that pulls matter together.
Magnetic Field
The space around a magnet where the magnetic force is active. Earth has a magnetic field and its extension into space helps protect us from space weather.
Meteor
The streak of light caused when a meteoroid enters a planet’s atmosphere and starts to burn from the heat of friction.
Solar System
A set that includes a star and all of the matter that orbits it, including planets, moons, asteroids, comets, and other objects.
Spacecraft
A vehicle used for traveling in space.
Supernova
The explosion of a star that makes it as bright as a whole galaxy.
Universe
All of space and time, and everything in it
X-Rays
Radiation with lots of energy made by very hot gases, stars, neutron stars, and gas around black holes.
Telescope
a usually tubular optical instrument for viewing distant objects by means of the refraction of light rays through a lens.
Mercury
The closest planet to the sun.
