The Solar System
Studying the asteroids
A few telescopes
Collisions
Asteroids or
Benoît Carry Astronomer at Paris Observatory
1/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
?
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Asteroids, what are they ?
2/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Asteroids, what are they ?
2/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Asteroids, what are they ?
2/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
1. The Solar System 2. Studying the asteroids 3. A few telescopes 4. The asteroid hazard 5. Protecting the Earth
3/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
1. The Solar System . Solar System inventory . Identifying the asteroids 2. Studying the asteroids 3. A few telescopes 4. The asteroid hazard 5. Protecting the Earth
4/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
What’s in the Solar System ?
5/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
What’s in the Solar System ?
5/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
What’s in the Solar System ?
5/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
What’s in the Solar System ?
5/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
What’s in the Solar System ?
5/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
What’s in the Solar System ?
5/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
What’s in the Solar System ? Type Star Planets Satellites Asteroids
Number 1 8 171 595 959
Examples Sun Mercury, Venus... Moon, Phobos... Ceres, Pluto, Halley...
6/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Size and distance references I. Distances • Sun-Earth – 1 UA 150 M km 8 min
@
c
• Sun-Jupiter – 5 UA ,
778 M km 43 min
@
c
• Sun-Neptune – 30 UA 4.5 G km 4h20
@
c
• Sun-Oort – 50 000 UA 7.5 P km 288 days 7/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
@
c
The Solar System
Studying the asteroids
A few telescopes
Collisions
Size and distance references II. Sizes • Ceres – (1) 950 km 0.1 × ♁
,
• Earth – ♁
12 756 km 1×♁
• Jupiter – X 139 822 km 11 × ♁
• Sun – 1 392 000 km 109 × ♁ 7/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Asteroids detection
Epoch 1
Epoch 2 Where is the asteroid ?
8/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Epoch 3
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Asteroids detection
8/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Asteroids detection
8/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Asteroids detection
8/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
1. The Solar System 2. Studying the asteroids . Insights on planetary formation . A melting pot of analyses 3. A few telescopes 4. The asteroid hazard 5. Protecting the Earth
9/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Planetary formation : Resume A step-by-step built : a. Gas & dust cloud contraction b. Disk formation c. Rotation, accumulation of material d. A star is born e. Accretion within the disk f. Planetary system
10/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Planetary formation : Resume A step-by-step built : a. Gas & dust cloud contraction b. Disk formation c. Rotation, accumulation of material d. A star is born e. Accretion within the disk f. Planetary system
10/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Planetary formation : Examples
11/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Planetary formation : Asteroids 1. Large population ◦ 600 000 objects (several millions) ◦ Wide range of compositions [rocks → ices] ◦ Wide range of heliocentric distances
2. Primitive population ◦ Small objects ◦ Internal energy ≈ null ◦ No endogeneous activity
. Direct witenesse of the early Solar System
12/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
A melting pot of analyses 1. Composition ◦ The most important in fine ◦ Conditions at formation I Map of the early Solar System
2. Dynamics ◦ Formation vs current location ◦ Asteroid-meteorite links I Impact threat
3. Physical properties ◦ Size, shape, spin ◦ Craters, seasons I Strong constraints on 1. & 2. 13/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
A melting pot of analyses 1. Composition ◦ The most important in fine ◦ Conditions at formation I Map of the early Solar System
2. Dynamics ◦ Formation vs current location ◦ Asteroid-meteorite links I Impact threat
3. Physical properties ◦ Size, shape, spin ◦ Craters, seasons I Strong constraints on 1. & 2. 13/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
A melting pot of analyses 1. Composition ◦ The most important in fine ◦ Conditions at formation I Map of the early Solar System
2. Dynamics ◦ Formation vs current location ◦ Asteroid-meteorite links I Impact threat
3. Physical properties ◦ Size, shape, spin ◦ Craters, seasons I Strong constraints on 1. & 2. 13/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Composition : Spectroscopy
14/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Composition : Spectroscopy
14/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Composition : Spectroscopy
14/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Dynamics : Meteorites
15/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Dynamics : Meteorites
15/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Dynamics : Meteorites
15/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Dynamics : Meteorites
15/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Dynamics : Meteorites
15/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Dynamics : Meteorites
15/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Physical properties : Density • Density ⇔ composition ◦ ◦ ◦ ◦
Ices : ρ ≈ 1 g.cm−3 Rock : ρ ≈ 2–3 g.cm−3 Metal : ρ ≈ 5 g.cm−3 Earth : ρ = 5.5 g.cm−3
• Density = Mass / Volume ◦ Satellites’ orbit → mass ◦ Disk-resolved images → volume
• Expected precision ? ◦ Asteroids are small ! ◦ 100 = 1 Euro @ 2 km ◦ Large telescopes required
16/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Physical properties : Density • Density ⇔ composition ◦ ◦ ◦ ◦
Ices : ρ ≈ 1 g.cm−3 Rock : ρ ≈ 2–3 g.cm−3 Metal : ρ ≈ 5 g.cm−3 Earth : ρ = 5.5 g.cm−3
• Density = Mass / Volume ◦ Satellites’ orbit → mass ◦ Disk-resolved images → volume
• Expected precision ? ◦ Asteroids are small ! ◦ 100 = 1 Euro @ 2 km ◦ Large telescopes required
16/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Physical properties : Density • Density ⇔ composition ◦ ◦ ◦ ◦
0.5"
Ices : ρ ≈ 1 g.cm−3 Rock : ρ ≈ 2–3 g.cm−3 Metal : ρ ≈ 5 g.cm−3 Earth : ρ = 5.5 g.cm−3
• Density = Mass / Volume N
◦ Satellites’ orbit → mass ◦ Disk-resolved images → volume
E
• Expected precision ? ◦ Asteroids are small ! ◦ 100 = 1 Euro @ 2 km ◦ Large telescopes required 0.5"
16/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Physical properties : Density • Density ⇔ composition ◦ ◦ ◦ ◦
0.5"
Ices : ρ ≈ 1 g.cm−3 Rock : ρ ≈ 2–3 g.cm−3 Metal : ρ ≈ 5 g.cm−3 Earth : ρ = 5.5 g.cm−3
• Density = Mass / Volume N
◦ Satellites’ orbit → mass ◦ Disk-resolved images → volume
E
• Expected precision ? ◦ Asteroids are small ! ◦ 100 = 1 Euro @ 2 km ◦ Large telescopes required 0.5"
VLT
16/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Physical properties : Density • Density ⇔ composition ◦ ◦ ◦ ◦
0.5"
Ices : ρ ≈ 1 g.cm−3 Rock : ρ ≈ 2–3 g.cm−3 Metal : ρ ≈ 5 g.cm−3 Earth : ρ = 5.5 g.cm−3
• Density = Mass / Volume N
◦ Satellites’ orbit → mass ◦ Disk-resolved images → volume
E
• Expected precision ? ◦ Asteroids are small ! ◦ 100 = 1 Euro @ 2 km ◦ Large telescopes required 0.5"
Keck VLT
16/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Physical properties : Density • Density ⇔ composition ◦ ◦ ◦ ◦
0.5"
Ices : ρ ≈ 1 g.cm−3 Rock : ρ ≈ 2–3 g.cm−3 Metal : ρ ≈ 5 g.cm−3 Earth : ρ = 5.5 g.cm−3
• Density = Mass / Volume N
◦ Satellites’ orbit → mass ◦ Disk-resolved images → volume
E
• Expected precision ? ◦ Asteroids are small ! ◦ 100 = 1 Euro @ 2 km ◦ Large telescopes required 0.5"
Keck VLT Orbite
16/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Physical properties : Density A
• Density ⇔ composition ◦ ◦ ◦ ◦
0.5"
B
Ices : ρ ≈ 1 g.cm−3 Rock : ρ ≈ 2–3 g.cm−3 Metal : ρ ≈ 5 g.cm−3 Earth : ρ = 5.5 g.cm−3
• Density = Mass / Volume N
◦ Satellites’ orbit → mass ◦ Disk-resolved images → volume
E
C
• Expected precision ? ◦ Asteroids are small ! ◦ 100 = 1 Euro @ 2 km ◦ Large telescopes required 0.5"
Keck VLT Orbit
16/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
1. The Solar System 2. Studying the asteroids 3. A few telescopes . Different classes of telescope . Space telescopes 4. The asteroid hazard 5. Protecting the Earth
17/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Different classes of telescope 1. 0.005 m aperture : eye • Used for eons • Precise, but not calibrated (subjective)
2. 0.5–2 m aperture– XIX century • Large field of view • Low sensitiveness
3. 4 m aperture – 1980s • Large and moderate field of view • Sensitive
4. 10 m aperture – 1990s • Small field of view • Sensitive and very high resolution 18/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Absorption (%)
Why a space telescope ? B VR I J H K
100
N
Q
50 Wavelength
0 0,1 Ultra-Violet
1 Visible
10 Near infrared
Mid infrared
19/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
100 μm Far infrared
The Solar System
Studying the asteroids
A few telescopes
Why a space telescope ?
19/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
1. The Solar System 2. Studying the asteroids 3. A few telescopes 4. The asteroid hazard . Collisions in the Solar System . On Earth too ? 5. Protecting the Earth
20/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Collisions everywhere... 1. Planet : Mercury 2. Planet : Venus 3. Planet : Mars 4. Asteroids 5. Callisto : Jupiter’s satellite 6. Mimas : Saturn’s satellite 7. Ob´eron : Uranus’ satellite Mercury 8. Comets & outer objects
21/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Collisions everywhere... 1. Planet : Mercury 2. Planet : Venus 3. Planet : Mars 4. Asteroids 5. Callisto : Jupiter’s satellite 6. Mimas : Saturn’s satellite 7. Ob´eron : Uranus’ satellite Venus 8. Comets & outer objects
21/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Collisions everywhere... 1. Planet : Mercury 2. Planet : Venus 3. Planet : Mars 4. Asteroids 5. Callisto : Jupiter’s satellite 6. Mimas : Saturn’s satellite 7. Ob´eron : Uranus’ satellite Mars 8. Comets & outer objects
21/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Collisions everywhere... 1. Planet : Mercury 2. Planet : Venus 3. Planet : Mars 4. Asteroids 5. Callisto : Jupiter’s satellite 6. Mimas : Saturn’s satellite 7. Ob´eron : Uranus’ satellite 8. Comets & outer objects
21/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Collisions everywhere... 1. Planet : Mercury 2. Planet : Venus 3. Planet : Mars 4. Asteroids 5. Callisto : Jupiter’s satellite 6. Mimas : Saturn’s satellite 7. Ob´eron : Uranus’ satellite Callisto 8. Comets & outer objects
21/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Collisions everywhere... 1. Planet : Mercury 2. Planet : Venus 3. Planet : Mars 4. Asteroids 5. Callisto : Jupiter’s satellite 6. Mimas : Saturn’s satellite 7. Ob´eron : Uranus’ satellite Mimas 8. Comets & outer objects
21/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Collisions everywhere... 1. Planet : Mercury 2. Planet : Venus 3. Planet : Mars 4. Asteroids 5. Callisto : Jupiter’s satellite 6. Mimas : Saturn’s satellite Oberon & Miranda
7. Ob´eron : Uranus’ satellite 8. Comets & outer objects
21/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Collisions everywhere... 1. Planet : Mercury 2. Planet : Venus 3. Planet : Mars 4. Asteroids 5. Callisto : Jupiter’s satellite 9P/Tempel 1
6. Mimas : Saturn’s satellite 7. Ob´eron : Uranus’ satellite 8. Comets & outer objects
21/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
...even very very close-by !
Moon
22/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Conclusions ? 1. Planets and satellites formed by collisions • Accretion mechanism • Most-likely formation scenario
2. Asteroids everywhere • 600 000 known • ∼10 000 monthly discovery !
3. Craters on every single planetary body • Planetary surfaces cribbled by impacts . and on Earth ?
. Past mechanism or still active ? • Seen in “real time” in 1994 (SL9 & Jupiter) • Lunar flashes 23/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Conclusions ? 1. Planets and satellites formed by collisions • Accretion mechanism • Most-likely formation scenario
2. Asteroids everywhere • 600 000 known • ∼10 000 monthly discovery !
3. Craters on every single planetary body • Planetary surfaces cribbled by impacts . and on Earth ?
. Past mechanism or still active ? • Seen in “real time” in 1994 (SL9 & Jupiter) • Lunar flashes 23/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Conclusions ? 1. Planets and satellites formed by collisions • Accretion mechanism • Most-likely formation scenario
2. Asteroids everywhere • 600 000 known • ∼10 000 monthly discovery !
3. Craters on every single planetary body • Planetary surfaces cribbled by impacts . and on Earth ?
. Past mechanism or still active ? • Seen in “real time” in 1994 (SL9 & Jupiter) • Lunar flashes 23/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Conclusions ? 1. Planets and satellites formed by collisions • Accretion mechanism • Most-likely formation scenario
2. Asteroids everywhere • 600 000 known • ∼10 000 monthly discovery !
3. Craters on every single planetary body • Planetary surfaces cribbled by impacts . and on Earth ?
. Past mechanism or still active ? • Seen in “real time” in 1994 (SL9 & Jupiter) • Lunar flashes 23/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Conclusions ? 1. Planets and satellites formed by collisions • Accretion mechanism • Most-likely formation scenario
2. Asteroids everywhere • 600 000 known • ∼10 000 monthly discovery !
3. Craters on every single planetary body • Planetary surfaces cribbled by impacts . and on Earth ?
. Past mechanism or still active ? • Seen in “real time” in 1994 (SL9 & Jupiter) • Lunar flashes 23/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Conclusions ? 1. Planets and satellites formed by collisions • Accretion mechanism • Most-likely formation scenario
2. Asteroids everywhere • 600 000 known • ∼10 000 monthly discovery !
3. Craters on every single planetary body • Planetary surfaces cribbled by impacts . and on Earth ?
. Past mechanism or still active ? • Seen in “real time” in 1994 (SL9 & Jupiter) • Lunar flashes 23/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Examples of terrestrial craters
Carancas crater, Perou I
Diameter : 13.5 m
I
Rims : 0.5 m
I
Age : 5 years
I
Meteorite : 1 m
24/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Examples of terrestrial craters
Chelyabinsk, Russia I
Diameter : 1 km
I
Rims : 0 m
I
Age : 3 months
I
Meteorite : 20 m
24/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Examples of terrestrial craters
Barringer Meteor Crater, USA I
Diameter : 1.18 km
I
Rims : 45 m
I
Age : 40 000 years
I
Meteorite : 50 m
24/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Examples of terrestrial craters
Tunguska event, Russia I
Diameter : 20-100 km
I
Rims : 0 m
I
Age : 102 years
I
Meteorite : ×10 m
24/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Examples of terrestrial craters
Manicouagan crater, Quebec I
Diameter : 100 km
I
Rims : 163 m
I
Age : 214 Millions years
I
Meteorite : 5 km
24/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Examples of terrestrial craters
Chicxulub crater, Mexico I
Diameter : 180 km
I
Rims : ...
I
Age : 65 Millions year
I
Meteorite : ∼10 km
24/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Sensitive effects on Earth Chicxulub and dinosaurs I
Giant impact
I
Probable “nuclear winter”
I
Compatible time line
What about us ? I
Frequency ?
I
Means of detection ?
I
Means of protection ?
25/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Impact frequency ye
ar
Impact every -4
10
-3
10
0
10
2
10
3
10
6
10
8
10
9
10
1m
10 m
100 m 1 km Meteorite size
26/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
10 km
100 km
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Impact frequency ye
ar
Impact every -4
hour
10
day
10
year
10
century
10
-3
0
2
3
millenium
10
1 Ma
10
100 Ma
10
4.5 Ga
10
6
8
9
1m
10 m
100 m 1 km Meteorite size
26/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
10 km
100 km
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Impact frequency ye
ar
Impact every -4
hour
10
day
10
year
10
century
10
-3
0
2
3
millenium
10
1 Ma
10
100 Ma
10
4.5 Ga
10
6
8
9
1m 10 m
10 m
100 m 1 km Meteorite size
10 km
100 m
1 km 10 km Crater size
100 km
26/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
100 km 1000 km
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Impact frequency ye
ar
Impact every -4
hour
10
day
10
year
10
century
10
Atmospheric explosion Small craters
-3
0
2
3
millenium
10
1 Ma
10
100 Ma
10
4.5 Ga
10
6
8
9
1m 10 m
10 m
100 m 1 km Meteorite size
10 km
100 m
1 km 10 km Crater size
100 km
26/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
100 km 1000 km
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Impact frequency ye
ar
Impact every -4
hour
10
day
10
year
10
century
10
Atmospheric explosion Small craters
-3
0
2
Tsunami Climate changes
3
millenium
10
1 Ma
10
100 Ma
10
4.5 Ga
10
6
8
9
1m 10 m
10 m
100 m 1 km Meteorite size
10 km
100 m
1 km 10 km Crater size
100 km
26/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
100 km 1000 km
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Impact frequency ye
ar
Impact every -4
hour
10
day
10
year
10
century
10
Atmospheric explosion Small craters
-3
0
2
Tsunami Climate changes
3
millenium
10
1 Ma
10
6
Mass extinction
8
100 Ma
10
4.5 Ga
10
9
1m 10 m
10 m
100 m 1 km Meteorite size
10 km
100 m
1 km 10 km Crater size
100 km
26/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
100 km 1000 km
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Impact frequency ye
ar
Impact every -4
hour
10
day
10
year
10
century
10
millenium
10
1 Ma
Atmospheric explosion Small craters Chelyabinsk
-3
0
Tunguska
2
Tsunami Climate changes
3
Meteor crater
6
10
Manicouagan
Mass extinction
8
100 Ma
10
4.5 Ga
10
Chicxulub
9
1m 10 m
10 m
100 m 1 km Meteorite size
10 km
100 m
1 km 10 km Crater size
100 km
26/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
100 km 1000 km
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Impact frequency -2
10 ar
Impact every ye
10
day
10
year
10
century
10
millenium
10
Megatons of TNT World nuclear arsenal
5
10
8
10
Atmospheric explosion Small craters Chelyabinsk
-3
0
Tunguska
2
Tsunami Climate changes
3
Meteor crater
10
8
100 Ma
10
4.5 Ga
10
9
1m 10 m
Manicouagan
Chicxulub
10 m
100 m 1 km Meteorite size
10 km
100 m
1 km 10 km Crater size
100 km
26/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Mass extinction
Golbal Mayhem
6
Nuclear winter
1 Ma
2
10
Hiroshima
-4
hour
0
10
100 km 1000 km
The Solar System
Studying the asteroids
A few telescopes
1. The Solar System 2. Studying the asteroids 3. A few telescopes 4. The asteroid hazard 5. Protecting the Earth . Real necessity or science fiction ? . Turino scale . There are solutions
27/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Shall we protect against asteroids ? I
Yes : There is a real threat. . . • Mass extinction • Millions of asteroids • Probability 6= null
I
No : . . . not at a human scale • • • .
I
Earthquake, tsunami, ... SIDA, alcoholism, car accident, war... 90% of asteroids known (50% with φ = 1 km) Aim : 99% in 2015-2020 (100% with φ = 100–200 m)
Overall... well... yes • Collect funds for fundamental research • Hollywood shots action movies
28/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Shall we protect against asteroids ? I
Yes : There is a real threat. . . • Mass extinction • Millions of asteroids • Probability 6= null
I
No : . . . not at a human scale • • • .
I
Earthquake, tsunami, ... SIDA, alcoholism, car accident, war... 90% of asteroids known (50% with φ = 1 km) Aim : 99% in 2015-2020 (100% with φ = 100–200 m)
Overall... well... yes • Collect funds for fundamental research • Hollywood shots action movies
28/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Shall we protect against asteroids ? I
Yes : There is a real threat. . . • Mass extinction • Millions of asteroids • Probability 6= null
I
No : . . . not at a human scale • • • .
I
Earthquake, tsunami, ... SIDA, alcoholism, car accident, war... 90% of asteroids known (50% with φ = 1 km) Aim : 99% in 2015-2020 (100% with φ = 100–200 m)
Overall... well... yes • Collect funds for fundamental research • Hollywood shots action movies
28/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Shall we protect against asteroids ? I
Yes : There is a real threat. . . • Mass extinction • Millions of asteroids • Probability 6= null
I
No : . . . not at a human scale • • • .
I
Earthquake, tsunami, ... SIDA, alcoholism, car accident, war... 90% of asteroids known (50% with φ = 1 km) Aim : 99% in 2015-2020 (100% with φ = 100–200 m)
Overall... well... yes • Collect funds for fundamental research • Hollywood shots action movies
28/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Shall we protect against asteroids ? I
Yes : There is a real threat. . . • Mass extinction • Millions of asteroids • Probability 6= null
I
No : . . . not at a human scale • • • .
I
Earthquake, tsunami, ... SIDA, alcoholism, car accident, war... 90% of asteroids known (50% with φ = 1 km) Aim : 99% in 2015-2020 (100% with φ = 100–200 m)
Overall... well... yes • Collect funds for fundamental research • Hollywood shots action movies
28/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Shall we protect against asteroids ? I
Yes : There is a real threat. . . • Mass extinction • Millions of asteroids • Probability 6= null
I
No : . . . not at a human scale • • • .
I
Earthquake, tsunami, ... SIDA, alcoholism, car accident, war... 90% of asteroids known (50% with φ = 1 km) Aim : 99% in 2015-2020 (100% with φ = 100–200 m)
Overall... well... yes • Collect funds for fundamental research • Hollywood shots action movies
28/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Shall we protect against asteroids ? I
Yes : There is a real threat. . . • Mass extinction • Millions of asteroids • Probability 6= null
I
No : . . . not at a human scale • • • .
I
Earthquake, tsunami, ... SIDA, alcoholism, car accident, war... 90% of asteroids known (50% with φ = 1 km) Aim : 99% in 2015-2020 (100% with φ = 100–200 m)
Overall... well... yes • Collect funds for fundamental research • Hollywood shots action movies
28/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Turino scale Turino scale Kinetic energy (MT)
10
8
6
5km 10
5
7
2
1km
1
10 5
4 100 1
100m
0
3
9 8
20m
-8
10
-6
10
-4
10
-2
10
>0.99
Impact probability
29/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Turino scale Turino scale Kinetic energy (MT)
10
8
6
5km 10
5
7
2
1km
1
10 5
4 100 1
100m
0
3
9 8
20m
-8
10
-6
10
-4
10
-2
10
>0.99
Impact probability
No Hazard 0 : No hazard
29/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Turino scale Turino scale Kinetic energy (MT)
10
8
6
5km 10
5
7
2
1km
1
10 5
4 100 1
100m
0
3
9 8
20m
-8
10
-6
10
-4
10
-2
10
>0.99
Impact probability
No Hazard 0 : No hazard
Normal 1 : Close encounter
29/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Turino scale Turino scale Kinetic energy (MT)
10
8
10
Astronomer Attention
6
5km 5
7
2
1km
1
10 5
4 100 1
100m
0
3
9 8
2 : Very close encounter 3 : 1% : Local destruction 4 : 1% : Regional destruction
20m
-8
10
-6
10
-4
10
-2
10
>0.99
Impact probability
No Hazard 0 : No hazard
Normal 1 : Close encounter
29/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Turino scale Turino scale Kinetic energy (MT)
10
8
10
Astronomer Attention
6
5km 5
7
2
1km
1
10 5
4 100 1
100m
0
3
9 8
2 : Very close encounter 3 : 1% : Local destruction 4 : 1% : Regional destruction
20m
Threatening : Large Object -8
10
-6
10
-4
10
-2
10
Impact probability
>0.99
5 : Regional - 10 years 6 : Global - 30 years 7 : Global - 100 years
No Hazard 0 : No hazard
Normal 1 : Close encounter
29/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Turino scale Turino scale Kinetic energy (MT)
10
8
10
Astronomer Attention
6
5km 5
7
2
1km
1
10 5
4 100 1
100m
0
3
9 8
2 : Very close encounter 3 : 1% : Local destruction 4 : 1% : Regional destruction
20m
Threatening : Large Object -8
10
-6
10
-4
10
-2
10
Impact probability
No Hazard 0 : No hazard
Normal 1 : Close encounter
>0.99
5 : Regional - 10 years 6 : Global - 30 years 7 : Global - 100 years
Certain Collision 8 : Local Destruction [10-103 ] years 9 : Regional devastation [104 -105 ] years 10 : Global cataclysm [105 ] years
29/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Proposed solutions 1. Atomic bomb – fast ◦ Destruct impactor ◦ Uncivilized
30/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Proposed solutions 1. Atomic bomb – fast ◦ Destruct impactor ◦ Uncivilized 2. Kinetic impact – fast ◦ Deviate impactor ◦ Easy and clean
30/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Proposed solutions 1. Atomic bomb – fast ◦ Destruct impactor ◦ Uncivilized 2. Kinetic impact – fast ◦ Deviate impactor ◦ Easy and clean 3. Thrusters – slow ◦ Deviate impactor ◦ Expensive & complicated
30/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
Collisions
Protecting the Earth
Proposed solutions 1. Atomic bomb – fast ◦ Destruct impactor ◦ Uncivilized 2. Kinetic impact – fast ◦ Deviate impactor ◦ Easy and clean 3. Thrusters – slow Yarkovsky effect
◦ Deviate impactor ◦ Expensive & complicated 4. Yarkovsky effect – slow ◦ Deviate impactor
Daily effect
Annual effect
◦ Expensive but green
30/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
The Solar System
Studying the asteroids
A few telescopes
The true solution
Call Bruce Willis : 424 288 2000
31/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Collisions
Protecting the Earth
The Solar System
Studying the asteroids
A few telescopes
Collisions
Miscellaneous information . Web pages • JPL Photojournal • Astronomy Picture of the Day • Universe today . Software • Celestia : 3D Solar System • Stellarium : Night sky . Centres
. Interested ?
◦ ObsPM : Paris Obs.
• Physics
◦ Univ. Paris 6,7,11
• Mathematics
◦ CEA
• Geology
32/32 Benoˆıt Carry, Astronomer at Paris Observatory, Orl´ eans, 05/22/2013
Protecting the Earth
