sun : terrestrial planets : jovian planets
TRANSCRIPT
Sun : Terrestrial planets : Jovian planets
5 AU
50 AU
500 AU
50,000 AU
Comet McNaught from Australia (January 2007)
Dust tail
Hydrogen envelope
Ion tail
Nucleus
Coma
Comet Halley (1986) Comet Hartley2 (2010)
Comet Nuclei
Comet Holmes (2007) : Coma and ion tail
Comet Hale-Bopp (1997) : dust tail and ion tail
Earthgrazer: The Great Daylight Fireball of 1972
Car damaged by Peekskill meteor (shown below)
Impact sites discovered since 1980
Chicxulub crater, Yucatan Peninsula, Mexico – 65 MY
Clearwater Lakes, Quebec, Canada – 290 MY
Meteor Crater AZ – 40,000 years
1200 meters
Torino Scale: Impact hazard associated with NEO
Kin
etic
Ene
rgy
(MT)
Impact probability
108
105
100
1
10-8 10-6 10-4 10-2 >0.99
No concern – Pay attention – Threatening – Certain impact
Meteorites
Stony Stony-Iron (pallasites)
Irons
Meteorites
Stony Stony-Iron (pallasites)
Irons
Achondrites Chondrites
Meteorites
Stony Stony-Iron (pallasites)
Irons
Achondrites Chondrites
Ordinary Chondrites
Carbonaceous Chondrites
Iron meteorite
Pallasite meteorite
Ordinary stone Meteorite
Achondrite
Ordinary Chondrite
Chondrule
Carbonaceous Chondrite
Primitive stones 52 87 85 (chondrites) Differentiated stones 1 9 12 Irons 42 3 2 Stony Irons 5 1 1 (pallasites)
Meteorite Abundances (%)
Finds Falls Antarctic
Primitive stones 52 87 85 (chondrites) Differentiated stones 1 9 12 Irons 42 3 2 Stony Irons 5 1 1 (pallasites)
Meteorite Abundances (%)
Finds Falls Antarctic
Primitive stones 52 87 85 (chondrites) Differentiated stones 1 9 12 Irons 42 3 2 Stony Irons 5 1 1 (pallasites)
Meteorite Abundances (%)
Finds Falls Antarctic
Primitive stones 52 87 85 (chondrites) Differentiated stones 1 9 12 Irons 42 3 2 Stony Irons 5 1 1 (pallasites)
Meteorite Abundances (%)
Finds Falls Antarctic
2004 FH
3753 Cruithne
1 Ceres 940
2 Pallas 580
4 Vesta 550
10 Hygeia 440
107 Camilla 250
87 Sylvia 225
12 Victoria 115
8 Flora 150
433 Eros 7x20x30
3476
4 Vesta
21 Lutetia
253 Mathilde
243 Ida (243) Ida 1 Dactyl
433 Eros
951 Gaspra
2867 Steins
25143 Itokawa
243 Ida
Dactyl
Kirkwood Gaps N
umbe
r of a
ster
oids
(p
er 0
.005
AU
bin
)
Distance (AU)
4:1 3:1 2:1
Kirkwood Gaps N
umbe
r of a
ster
oids
(p
er 0
.005
AU
bin
)
Distance (AU)
4:1 3:1 5:2 7:3 2:1
Kirkwood Gaps N
umbe
r of a
ster
oids
(p
er 0
.005
AU
bin
)
Distance (AU)
4:1 3:1 5:2 7:3 2:1 11:5
Kirkwood Gaps N
umbe
r of a
ster
oids
(p
er 0
.005
AU
bin
)
Distance (AU)
4:1 3:1 5:2 7:3 2:1 8:3 11:5
Kirkwood Gaps N
umbe
r of a
ster
oids
(p
er 0
.005
AU
bin
)
Distance (AU)
4:1 3:1 5:2 7:3 2:1 10:3 8:3 11:5
Orbital resonance
25143 Itokawa
Asteroids composition albedo population C-type carbonaceous 0.03 75% S-type Fe + Mg silicates 0.10 – 0.22 17% M-type Fe +Ni alloy 0.10 – 0.18 8%
S M C
popu
latio
n
Distance (AU) 2.0 2.5 3.0 3.5
S M C