asteroid--one of the small planets occupying orbits mainly between Mars and Jupiter.
astronaut--a space traveler
astronomer--someone who studies the heavenly bodies
Black hole - An object whose gravity is so strong that the escape velocity exceeds the speed of light.
comet--A small body of ice and dust in orbit around the Sun. While passing near the sun, a comet's vaporized ice become its "tail".
Constellation - A group of stars that make a shape, often named after
mythological characters, people, animals, and things.
Core - The innermost layer of a planet or star.
Corona - The Sun's outer atmosphere.
crater- A hole caused by a meteorite crashing into the moon's surface or by a volcano exploding.
Earth--The fifth largest planet of the solar system. It is the third planet from the sun.
galaxy--one of the vast number of systems containing stars, star clusters
Halley's Comet--He observed the great comet of 1682 and calculated its orbit and predicted its return in 1758.
Jupiter--It is the fifth planet from the sun. Jupiter has a Great Red Spot. It is the first of the outer planets, and is the largest of all the planets.
lunar eclipse--A darkening of the moon caused by the passing of the earth between the sun and the moon.
Mars-- Mars is the inner planet farthest from the sun. It is called the Red Planet because its soil is red.
Mercury-- Mercury is the planet closest to the sun. It is the smallest of the inner planets.
meteor--It falls across the dark sky, leaving a silvery trail behind. It may look like a shooting star, but really this is a meteor. Meteors are the junk of the Solar system.
meteorite--A part of a meteoroid that survives through the Earth's atmosphere.
meteoroid--A small rock in space.
Moon--The moon is Earth's natural satellite. It takes the moon 27 days and 8 hours to circle the Earth.
Neptune--It takes 165 years to go around the sun. It is the eighth planet. Of the four giant planets, it is farthest away from the sun. Neptune has 3 known satellites.
orbit--The path of an object that is moving around a second object or point.
phases- The different shapes we see as the moon moves around the sun.
Pluto--Pluto still remains a mystery to scientists. It is the ninth planet/
satellite--A body that revolves around a larger body
Saturn--Saturn isn't the only planet with rings. It is the sixth planet from the sun. Saturn is the second largest planet in our solar system.
solar eclipse--A darkening of the sun caused by the passing of the moon between the sun and the earth.
sun--The central controlling body of the solar system, lying at the principal focus of all planetary orbits. It is also a star.
Uranus--This planet was discovered 200 years ago. It is our seventh planet. Uranus is the third of the four big outer planets. It is a small giant-only four times bigger than Earth. It has rings.
Venus--When you look up at the sky, the brightest objects are the sun and the moon. The next brightest is Venus. It is called the Evening Star.
