Debris
• Asteroids
• Comets
All can potentially become meteorites (shooting stars)
The solar system’s very own “left-overs.”
Pockets form from intense heat of entry into our atmosphere
Iron Meteorite
Asteroid Figure 26-16
AsteroidsAsteroid Gaspra versus Mar’s moons Pheobos and Diemos
Suspicious Asteroid Dactyl
Suspicious Asteroid Dactyl“Open the Pod Bay Doors, Hal.”
America From Space
Crater Remnant From Space
Meteor Crater, Arizona
Impact Site, Austrialia
Impact Site, Siberia
Ancient Impact Site
Ancient Impact Crater
Twin Impacts in Canada
Dinosaur Killer Beneath Gulf of Mexico
Meteor Shower Radiant
Comet Hyakutake 1996
Table 26.1Meteor Shower Dates and Comet Coincidences
Kirkwood GapsResonances with the Orbit of Jupiter
Figure 26-12
Cometary OriginsThe Oort Cloud
Multiple Impact Site
Comet Shoemaker-Levy 9
Comet ImpactComets are likely
responsible for bringing
the materials necessary
for life to evolve on
earth.
(water, ices and
organic molecules)
Icy Meteorites (Comets)
A Tale of TailsI. Gas Tail Points Away From
The Solar Wind
(charged particles, ions)
II. Dust Tail Points Along
The Orbital Path
(neutral debris, dust)
Comet Tail Evolution
Comet HalleyNucleus and Chemical Composition
Web ResourcesComet Observations
http://encke.jpl.nasa.gov
Minor Planet Center
http://cfa-www.harvard.edu/cfs/ps/mpc.html
Satellite Tracking Information
http://liftoff.msfc.nasa.gov/academy/rocket_sci/satellites
http://www2.satellite.eu.org/sat/vsohp/satintro.html