1. Space! Comets Asteroids Meteors

2. Inertia The tendency of a moving object to continue in a straight line or a stationary object to remain in place The more mass an object has, the more inertia it has. The more inertia an object has the harder it is to start/stop it. Inertia keeps the planets moving forward

3. Gravity A force that pulls objects towards each other. Gravity from the sun keeps the planets from floating out into space Strength of gravity depends on the masses and distance between the objects.

4. Gravity and Inertia Gravity and Inertia work together to keep the planets in orbit around the sun

5. Law of Universal Gravitation In Newton's equation, F is the gravitational force, G is a constant of proportionality, M and m are the two masses exerting the forces, and r is the distance between the two objects.

6. Comets Chunks of ice & space dust flying through space. * Elliptical Orbit around the Sun. * Part of our Solar System that orbits in and out. We can see it coming and going for days/weeks/months. * Solar wind burns off tail. Tail points away from the Sun.

8. http://cse.ssl.berkeley.edu/SegwayEd/lessons/cometstale/frame_orbits.html

9. http://science.nasa.gov/science-news/science-at-nasa/2007/01oct_encke/ “On April 20, 2007, the comet (Encke) had just dipped inside the orbit of Mercury, perilously close to the sun, when a solar eruption struck and literally tore the comet's tail off. This surely has happened to comets before, but for the first time in history a spacecraft was watching. NASA's STEREO-A probe recorded a fantastic movie of the collision. “

10. http://www.windows.ucar.edu/tour/link=/comets/comets.htm l

11. This image of the Hale-Bopp comet was taken on March 7, 1997. The comet is currently as far away from the Sun as our Earth is (1 astronomical unit). The yellow lines show where the comet has extensive outbursts of dust from its center or nucleus. This is very unusual because comets normally don't spew out this much dust at this distance. The image was taken by H Fukushima, M Takata, and D Kinshita. National Astronomical Observatory of Japan

12. Asteroids Chunks of Rock floating in space. Not spherical (ball-shaped like a planet). No volcanic activity Some large enough to have gravity. Most orbit the Sun between Mars & Jupiter – Asteroid Belt 26 asteroids are 200 Km long! Most more than 100 Km long!

13. http://en.wikibooks.org/wiki/Wikijunior:Solar_System/Asteroid_belt Most is empty space. Put all the asteroids together, they would still be smaller than Earth’s Moon. About 40,000 asteroids are more than ½ mile long!

14. Stoney asteroid 243 Ida and its satellite Dactyl (more information and orbit).243Idainformationorbit

16. Meteoroid Chunks of Rocks & Metals that float around in space Come from Asteroid Belt (broken from asteroids) Broken off from planets or comets Size: small rock or pebble. http://www.solarviews.com/eng/meteor.htm

17. Meteors Chunks of Rocks & Metal that fall into Earth’s atmosphere & burn up Meteoroids that are pulled in by E’s gravity Burn up when hit Earth’s atmosphere We see as “falling stars” – Meteor Showers http://www.star-bits.com/ID.htm

18. A detailed shot of a meteor, taken during the Leonid meteor shower in mid- November. Image Showing Meteors of the Leonid Meteor Shower, taken from Space. http://www.moonglow.net/ccd/picture s/meteors/index.html

19. Meteorite Meteoroid that does not burn up all the way. Hits the E’s surface. Very small, hit very fast. Most hit water, some land – causes craters Craters on Moon – from Meteorites

20. The Barringer Impact Crater in Arizona, USA. Note that it is 1.2km in diameter and has a maximum depth of 183 meters. It was created by a meteorite of 40 meters in diameter impacting at a speed of 11 km/second.

21. Meteoroid – rock still in space (Android phone satellite is in space) Meteor – rock that burns up in Earth’s atmosphere (OR it could burn up) Meteorite – rock that lands on Earth (“Are you alright?” “you have the right to keep it!”)

22. http://cse.ssl.berkeley.edu/SegwayEd/lessons/ CometsTale/com.htmlhttp://cse.ssl.berkeley.edu/SegwayEd/lessons/ CometsTale/com.html Comet Game http://cse.ssl.berkeley.edu/SegwayEd/lessons/c ometstale/frame_gallery.htmlhttp://cse.ssl.berkeley.edu/SegwayEd/lessons/c ometstale/frame_gallery.html Comet history pics