1. The luminous celestial body around which Earth and other planets revolve and receive heat and light! Sun

2. Star A self-luminous celestial body consisting of a mass of gas held together by its own gravity in which the energy is generated by nuclear reactions in its interior

3. Dwarf Planets Objects that were bigger than small solar system bodies such as comets and asteroids but not quite planets. There are five recognized dwarf planets: Pluto, Ceres, Eris, Makemake & Haumea.

4. Planet Any of the large celestial bodies that revolve around the Sun in the Solar System

5. Inner Planet Any of the rocky, terrestrial planets of Mercury, Venus, Earth, and Mars whose orbits range is within the asteroid belt

6. Outer Planet Any of the planets Jupiter, Saturn, Uranus, and Neptune whose orbits lie beyond the asteroid belt

7. Moons Moons are a natural satellite of a planet Earth’s moon (natural satellite) revolves around Earth from west to east

8. Galilean moons The four largest moons of Jupiter

9. Meteoroid A natural chunk of rock or dust existing outside Earth’s atmosphere

10. Meteor Small meteoroid that burns upon entry of Earth’s atmosphere

11. Meteorites Remains of meteoroids that strike the surface of Earth or the Moon

12. Asteroid Piece of rock or metal made up of material similar to that which formed the planets that orbit the Sun

13. Comet Consists primarily of ice, dust, and rock whose orbit is a long narrow ellipse

14. Orbit A curved path followed by a satellite as it revolves around an object in space

15. Gravity The force of attraction that pulls objects toward each other

16. Solar System The Sun together with the group of planets that are held by its attraction and revolve around it!

17. Space Probe An unmanned spacecraft designed to explore the Solar System and transmit data back to Earth

18. Space Shuttle A reusable spacecraft designed to transport people and cargo between Earth and space

19. Space Station A large artificial facility designed to be occupied for long periods and to serve as a work space to conduct research

20. Rocket A spacecraft that gets power from an engine full of chemical propellants

21. Rotation The spinning of Earth on its axis that causes day and night to occur

22. Revolution Earth’s year-long elliptical orbit around the Sun

23. NASA National Aeronautics and Space Administration; Founded to combine all of the separate rocket development teams in the US to create new rockets.