1. Starting Line 1. turn in Homework #1 2. book check 3. topic selections
Planetary Sciences

2. Asteroids 2003 semimajor axis
Planetary Sciences

3. Planetary Sciences

4. Asteroids 2003 semimajor axis
Planetary Sciences

5. Asteroids 2009 semimajor axis
Jupiter
Trojan
Asteroids
Planetary Sciences

6. Lagrangian Points
where objects feel no net force in rotating frame: gravitational force of two masses cancels centrifugal force because of rotation
5 per two body system
Trojan asteroids at Jupiter (~3000), Mars (4), Neptune (6)
small moons at Sat/Tethys (Telesto+Calypso) and Sat/Dione(Helene+Polydeuces)
Earth orbiting spacecraft
L1 L2 L3 unstable … L4 L5 stable
SOHO
WMAP
Planetary Sciences

7. Planetary Sciences

8. KBOs and Comets 2003 KBOs red: classical KBOs white: Plutinos
magenta: scattered disk
orange tri: Centaurs
cyan tri: “unusual”
COMETS
solid blue sqr: numbered
open blue squ: others
Planetary Sciences

9. KBOs and Comets 2009 KBOs red: classical KBOs white: Plutinos
magenta: scattered disk
orange tri: Centaurs
cyan tri: “unusual”
COMETS
solid blue sqr: numbered
open blue squ: others
more objects, not just pencil beams, pencil beams have spread, blue planets have moved,Pluto/KBOs have moved
Planetary Sciences

10. KBOs and Comets 2009 Plutinos/TNOs 1093 known Pluto Quaoar Ixion
Varuna
Orcus
Centaurs/SDOs
242 known
Chiron
Sedna
Nessus
Asbolus
Eris
TNO = Trans Neptunian Object
SDO = Scattered Disk Object
Planetary Sciences

11. TNOs/SDOs and Friends
Hydra
Nix
Planetary Sciences

12. Pluto Has 3 Moons!
Nix = mother of Charon … Hydra = guardian of underworld with 9 heads
Planetary Sciences

13. The “New” Solar System KBO Plutino Dwarf Planet Eris Plutoid
but wait, there’s more …
Planetary Sciences

14. The Outer Limits
Planetary Sciences

15. Hyakutake and Hale-Bopp
Planetary Sciences

16. Comet SOHO-6
white spot is size of Sun … tail 2X as long as Sun’s diameter
Planetary Sciences

17. Asteroids, KBOs, Oort Cloud
Asteroid Belt Kuiper Belt Oort Cloud
Orbital a 2.1 – 3.3 AU 30 – 100+ AU ~ 50,000 AU
Orbital e 0.0 – medium nearly 1.0
Orbital i low medium any!
Composition rocky rocky/icy icy/dusty
Planetary Sciences

18. Comet Exploration Exploration Halley Giotto, Vega
Tempel 1 Deep Impact … dropped a bullet
Wild 2 Stardust … sample return
2006 Stardust results indicate some grains from other stars captured from Wild 2 into aerogel
but most grains were (surprisingly) from both hot and cold environments in our early Solar System
conclusion: early SS was a mess with radical transport of cometary material at early stages
Planetary Sciences

19. Comet Damage
Planetary Sciences

20. Comet Damage
Planetary Sciences

21. Comet Damage: Tunguska 1908
Planetary Sciences

22. Asteroids … Bye Bye Dinosaurs
65 million years ago
Planetary Sciences

23. Game Over?
Planetary Sciences

24. Location, Location, Location
Planetary Sciences

25. Jovians Good or Bad?
Planetary Sciences

26. Disk: Protostellar or Debris?
Planetary Sciences

27. Fomalhaut Planet background star movie
Planet is just inside ring edge / orbital period 872 years
background star
movie
Planetary Sciences

28. Homework #2 Calculate the space densities in units of #objects
per cubic km of Main Belt asteroids, KBOs, and
Oort Cloud comets. Assume the following:
a. Asteroid Main Belt is a disk containing 106 objects
stretches from 2 AU to 3 AU and is 1 AU thick
b. Kuiper Belt is a disk containing 105 objects
stretches from 30 AU to 100 AU and is 10 AU thick
c. Oort Cloud is a sphere containing 1012 objects
stretches from 20,000 AU to 100,000 AU
DUE THURSDAY, JANUARY 22
Planetary Sciences