A rocky space object that can be a few feet wide to several hundred miles wide. Most asteroids in our solar system orbit in a belt between Mars and Jupiter.
A person who travels in space.
Scientist who observes and studies planets, stars, and galaxies.
All the gases which surround a star, like our Sun, or a planet, like our Earth.
An imaginary straight line around which an object spins.
The tiny building block that makes up everything.
Living things that have only one cell and are so small they can only be seen with a microscope.
An invisible object in outer space formed when a massive star collapses from its own gravity. A black hole has such a strong pull of gravity that not even light can escape from it.
To make less clear, to run together.
BIG BANG THEORY
A theory that says the Universe began with a super-powerful explosion.
A flash of lightning.
A very large piece of rock.
Easy to break or crack.
To swell or stick out; the part that swells or sticks out.
A metric temperature scale in which water freezes at 0 degrees and boils at 100 degrees.
To fall down or fall to pieces.
A crash or forceful joining together.
A big ball of dirty ice and snow in outer space.
An astronaut from the former Soviet Union or present day Russia.
A hole caused by an object hitting the surface of a planet or moon.
Broken, scattered remains; rubble; pieces of rubbish or litter.
To discover something which is hidden or unknown.
Shaped like an egg that has ends which are equal.
The power to do work.
Everything that surrounds anything.
To make larger.
A broken piece of something.
Anything that is burned to give heat or power.
A giant collection of gas, dust, and millions or billions of stars.
An invisible form of energy that is given off by atoms.
An empty space.
A form of matter which is not a liquid or a solid. A gas will spread out to fill up all of the space that is open to it.
The invisible force between objects that makes objects attract each other.
The attraction that one object has for another object due to the invisible force of gravity.
A very, very strong windstorm where the wind blows in circles at more than 46 kilometers per hour. Heavy rains often come with the winds.
1,000 meters. A kilometer equals 0.6214 miles.
The distance light can travel in one year, which is 9,500,000,000,000 kilometers.
The section of the Apollo spacecraft designed to land on the Moon.
The car-like vehicle used by Apollo astronauts while exploring the Moon's surface.
The amount of matter in an object.
What all things are made of.
An object from space that becomes glowing hot when it passes into Earth's atmosphere.
A piece of stone or metal from space that falls to Earth's surface.
A piece of stone or metal that travels in outer space.
A part of a set that can be arranged together in different ways.
Old stories that usually explain how something came to be.
The National Aeronautics and Space Administration which is in charge of all space programs for the United States.
A process where atoms are joined and tremendous amounts of energy are released.
The path followed by an object in space as it goes around another object; to travel around another object in a single path.
A very, very tiny piece of matter such as an electron, proton, or neutron found inside of an atom.
Cargo which is carried on the Space Shuttle.
A person who studies physics.
The study of how objects (from the very tiny to the very big) behave.
Large pieces of flat land.
The point at either end of the invisible line known as the axis. Planets have a south pole and a north pole.
A type of energy that is made by charged particles such as electrons moving back and forth.
The return of a spacecraft into Earth's atmosphere.
To throw back light, heat, or sound.
Can be used again.
To move in an orbit or circle around something.
To turn around a center point, or axis, like a wheel turns on a bicycle.
An object that moves around a larger object. There are natural satellites such as moons and there are man-made satellites such as the Hubble Space Telescope.
Going in many different directions.
Having to do with the Sun.
A storm or eruption of hot gases on the Sun.
Streams of gas particles flowing out from the Sun.
An unmanned research craft sent into space.
The picture produced by a spectroscope.
An instrument that breaks up the white light from a star into its different colors.
A dark area on the Sun's surface that is cooler than the area around it. Sunspots are caused by magnetic storms on the Sun.
An explosion of a star that causes the star to shine millions of times brighter than usual.
A device which creates a larger image of a far away object.
An invisible form of energy which is given off by the Sun. Ultraviolet rays cause people to get sunburned.
The huge space which contains all of the matter and energy in existence.
A piece of low land lying between hills or mountains.
Something used to carry people and things over land or in space.
Able to be seen.
An opening in a planet's surface through which hot liquid rock is thrown up.
Water which is in the form of a gas.
Having little or no weight; not feeling the effects of gravity.
An invisible form of energy which can go through most solid objects.