1. Solar system vocab

2. geocentric system Ptolemy – 140 A.D. Greek Astronomer believed that Earth was the center of the universe

3. heliocentric system Nicolaus Copernicus – 1500s Polish astronomer- thought that the sun is at the center of the system- current model thanks to Galileo looking through telescope

4. solar system Large planetary system with many smaller planetary systems and objects (planets and their moons)

5. ellipse elongated circle, oval shape Path of orbit Not a perfect circle

6. nuclear fusion 2 hydrogen = helium= sun H H He

7. core #5 on picture nuclear fusion reactions = energyfusion reactions core is a very dark place! Made of Plasma

8. Photosphere #4 on picture Sphere that makes light Part we can actually see

9. chromosphere #2 on picture Middle layer Means color

10. corona #1on picture Outer layer looks like a halo or crown Only visible during eclipses

11. Sunspot #3 on picture Areas of gas on the sun that are cooler Look darker

12. prominence #6 on picture Huge loop of gas

13. solar wind Corona sends our a stream of electrically charged particles aurora borealis- northern lights

14. solar flare Huge explosions on the sun

15. terrestrial planets Mercury, Venus, Earth & Mars Four inner planets are small and have rocky surfaces

16. Gas giants Jupiter, Saturn, Uranus & Neptune Large outer planets with stronger gravity Keeps gases from escaping

17. rotation Spinning motion of a planet about it’s own axis ONE DAY 23 hr 57 min 4 sec (Earth) DIFFERENT FOR EACH PLANET

18. satellite Any object that revolves around another object in space Natural satellite = moon Artificial satellite= machine (cell phone signals)

19. revolution One year Earth 365.25 days (365) February 29 2008 leap year every 4 th year Movement of an object going around another object

20. retrograde rotation Venus- travels east to west= clockwise Opposite direction of most planets It’s day is longer than it’s year

21. greenhouse effect Carbon dioxide traps heat in the atmosphere Venus’ surface becomes hotter and hotter Trapping heat

22. mnemonic device My Very Educated Mother Just Served Us Nine Pizzas Mercury Venus Earth Mars Jupiter Saturn Uranus Neptune Pluto