September 2011 Mirel Birlan - IMC2011-Sibiu 1
Near-Earth Asteroidsas source of meteors
Mirel BIRLAN
Institut de Mécanique Céleste et de Calculs des Ephémérides
Observatoire de Paris,
CNRS UMR 8028
e-mail: [email protected]
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Solar SystemMercure
Venus
Terre
Mars
Jupiter
Saturn
Uranus
Neptune
(cf UAI, Res 5, 2006)
Dwarf planets: Pluton, Cérès, …
Asteroids &
Near-Earth
Objects…
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ESO-La Silla MPG/WFI 2.2 m telescope (12 Mars 2008)
Credits:
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Statistics (April 17, 2009):
NEA – 6,113 objects
PHA – 1,041 objects
Discovery statistics for the
Main Surveys of NEAs
Why asteroids during IMC?
• Origin of Meteorites?
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Courtesy: Mathieu Gounelle
Why asteroids during IMC?
• Physical properties of asteroids
<=>constrains for meteoroids (meteors and
meteorites)
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Example: porosity
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SpeX 0.8-5.4 micron Medium-Resolution
IRTF Middle-class telescope (aperture = 3 m)
Mauna Kea, Hawaii
Infrastructure:•Two(One) PC’s (Linux OS) Polycom conference system •Three regular internet connections •Telephone (backup)•Connections via ssh or vnctunnels
Spectroscopy of NEAs(Visible & Near Infra-Red Regions)
Videoconference
system
Spectrograph
acquisition terminal Guiding camera
display
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MOVIE, DAYLIGHT RUN FROM MEUDON
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SPECTROSCOPYATMOSPHERIC TRANSPARENCY
Atmospheric Molecules:
H2O, O3, CO2, O2, NO2,
H2O
CO2
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NEOs spectra-
Exemples
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What is a Cosmochemical element ?
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Classification des astéroïdes
Spectre du visible et de l’infrarouge proche
Classification des oiseaux
DeMeo et al, Icarus, 2009
Établir l’ADN des astéroïdes par le
biais de la planétologie comparée!
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Statistique =>
(V+NIR data)
Taxonomie(The alphabet of asteroids)
DeMeo et al Icarus 2009
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Link between asteroids and meteorites (meteors)?
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Basalts (HED)
Carbonaceous
chondrites
Good Fit for some of classes
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Is the spectroscopy of meteors a
good/real chalange?
OC meteorite spectrum
Yes, especially for CC composition!
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Conclusions
• Meteorites offer laboratory measurementsfor mineralogical modeling of asteroids
• Friable/fluffy meteorites are rare/inexistent
• Spectroscopy of meteors may bring new observational data concerning the chemical structure of meteoroids
SIBIU
CUSSAC
50 m2009 DD45 (low albedo)
SIBIU
20 m (S-type asteroid) 2009 DD45
(real size)
SIBIU
