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GEOL3045: Planetary Geology. Lysa Chizmadia Asteroid Belt. Mars Landslides:. Image from: http://gizmodo.com/363517/reconnaissance-orbiter-captures-live-north-pole-avalanche-on-mars. Summary: Planetarium. Ecliptic. Milky Way.
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GEOL3045: Planetary Geology Lysa Chizmadia Asteroid Belt
Mars Landslides: Image from: http://gizmodo.com/363517/reconnaissance-orbiter-captures-live-north-pole-avalanche-on-mars
Summary: Planetarium Ecliptic Milky Way Image from: http://images.google.com/imgres?imgurl=http://documents.wolfram.com/applications/astronomer/Notebooks/NBMLImages/GraphicsGallery/GraphicsGallery_27.gif&imgrefurl=http://documents.wolfram.com/applications/astronomer/Notebooks/GraphicsGallery.html&h=251&w=459&sz=6&hl=en&start=41&um=1&tbnid=LSeB11GRCpj2-M:&tbnh=70&tbnw=128&prev=/images%3Fq%3DNight%2Bsky%2Becliptic%2Bmilky%2Bway%26start%3D40%26ndsp%3D20%26um%3D1%26hl%3Den%26client%3Dsafari%26rls%3Den%26sa%3DN
Introduction • Main Belt 2-4 AU • Total mass < Moon • Four largest, >50% of mass • 1 Ceres: ~950 km diameter (33%) • C-type • 4 Vesta: 460-580 km diameter (9%) • V-type • 2 Pallas: 500-570 km diameter (7%) • C-type • Inclination = 34.8° (~ Pluto) • 10 Hygiea: 350-500 km diameter (3%) • C-type Image from: http://en.wikipedia.org/wiki/Asteroid_belt
Detection www.sas.org/.../Feature_ 1_Fig_4_May_2007.jpg
C-type: 75% of asteroids Extremely dark (albedo 0.03) ~ Carbonaceous chondrites S-type: 17% of asteroids Moderately bright (albedo 0.10-0.22) Silicates + FeNi metal M-type: 8% of asteroids Very bright (albedo 0.10-0.18) FeNi metal V-type: ~ 4Vesta Moderately bright (albedo 0.10-0.22) ~ S-type w/ more px HED meteorites Spectral Classes
Spectroscopy Images from: http://www.noao.edu/education/asteroids/files/Asteroid-Spectra.pdf
Spectroscopy Images from: http://www.noao.edu/education/asteroids/files/Asteroid-Spectra.pdf
Distribution of Classes Image from: www.britannica.com/ eb/art/print?id=3485
Orbital Dynamics Kirkwood Gaps Eccentricity Inclination Images from: http://en.wikipedia.org/wiki/Asteroid_belt
Collisions 60-1000 tons of material per day intersect with Earth’s atmosphere Most is < grain of sand Velocities: 11-14 km/s Zodiacal Light Image from: http://en.wikipedia.org/wiki/Asteroid_belt Images from: http://www.psi.edu/hartmann/pic-cat/asteroids.html
Impact Probability Images from: http://www.ruf.rice.edu/~leeman/geol108_impacts.html
Summary • Most in main belt 2-4 AU • Total mass < Moon • 4 largest asteroids >50% mass • 4 main spectral types of Asteroids • C-type: carbonaceous chondrites • S-type: ordinary chondrites • M-type: metallic meteorites • V-type: HED meteorites