1. Solar System “Fluff” Pt. 2 The fluffier fluff.

2. Comets. Snowballs of DOOM!!!

4. Anatomy of a comet  Nucleus (1 – 100 km)  Coma (100,000 km)  Tails (1 – 500 million km)  Dust Tail  Ion Tail  Hydrogen Envelope (Cloud)  10 million – 100 million km

5. The Nucleus  Heart of the comet  Consists of:  Dust  Ice (H 2 O)  Other ices (CO 2, CH 4, NH 3, etc.)  Can appear VERY dark! (<10% reflectivity)

6. The Coma  Dense “Atmosphere” of materials surrounding nucleus.  Consists of vaporized materials from the nucleus as the comet approaches the sun  Comets have extremely low gravity  Cant keep the material close, or even hang on for long!  The Coma can be larger than the sun!

7. IonDust The Tails!  Gases from comet ionized by UV from sun  Magnetic field from solar wind pushes them back  Solar photons strike the material from the coma  This tail curves, due to the comets motion

8.  Halley’s

9. Trans-neptunian objects (TNO) ANY object that is part of the solar system and beyond the orbit of Neptune. Three subcategories Kuiper Belt Scattered Disc: Oort Cloud: All objects are primarily Icy, with frozen volatiles (methane, ammonia, etc.), some rock

10. The Kuiper Belt Consists of Objects from 30 – 50 A.U KBO = Kuiper Belt Object Hypothesized in 1930 Discovered in 1987 Over 100,000 KBOs larger than 100km Most are resonant with Neptune’s orbit

11. The Scattered Disc  Region primarily beyond the Kuiper Belt  Dynamic –  objects are not locked into resonance like KBOs  Most comets are believed to originate from this region  First designated in the late 90’s  Only very recently officially accepted

12. A sampling  more

13. The Oort cloud Farthest reaches of the solar system Objects up to 1 light year away (50,000 A.U.) Spherical in structure, instead of flat, disc shaped regions May have formed as a result of interactions with nearby stars (pulling objects out from the solar system)

16. Orbits of comets  HIGHLY elliptical

17. Bringers of Life (not doom)  Many impacts of early earth were comets  Thought to have contributed 3 things to early Earth  Water (comets are very icy)  Organic molecules (Comets contain precursors)  Perhaps even fully formed amino acids  Much research is still being done.

18. Mission: Deep Impact  impact

20.  Shoemaker-levy

21. Hyakutake  360 million km tail

22.  Not a spaceship… Hale-Bopp