1.Asteroids Lecture 7Tuesday, November 12 2013Dr Harold Clenet, EPSL, EPFL

2. What is an asteroid?Tuesday, November 12 20132Dr Harold Clenet, EPSL, EPFL 3. OutlineDiversity among the asteroids The electromagnetic spectrum and asteroids characteristics Asteroids families Some physical propertiesTuesday, November 12 2013Where do the asteroids come from? At the beginning of our Solar System From planetesimals to planetary embryos and asteroids Detection of asteroidsAsteroids and society Asteroids as hazards Asteroids as resources3Dr Harold Clenet, EPSL, EPFL 4. At the beginning of our solar systemTuesday, November 12 20134Dr Harold Clenet, EPSL, EPFL 5. At the beginning of our solar systemDiscs around young stars in Orion nebula (HST image)Tuesday, November 12 20135Dr Harold Clenet, EPSL, EPFL 6. At the beginning of our solar systemDisc around the young star AU Mic (Keck telescope)Vertical structureAccretion of planetesimals Tuesday, November 12 20136Dr Harold Clenet, EPSL, EPFL 7. From planetesimals to planetary embryos and asteroidsGrowth process for planetary embryosTuesday, November 12 20137Dr Harold Clenet, EPSL, EPFL 8. From planetesimals to planetary embryos and asteroidsThe small Mars problem and the Grand Tack ScenarioTuesday, November 12 20138Dr Harold Clenet, EPSL, EPFL 9. Detection of asteroidsGiuseppe Piazzi (1746-1826)Tuesday, November 12 20139Dr Harold Clenet, EPSL, EPFL 10. Detection of asteroidsTuesday, November 12 201310Dr Harold Clenet, EPSL, EPFL 11. Detection of asteroidsTuesday, November 12 201311Dr Harold Clenet, EPSL, EPFL 12. Detection of asteroidsTuesday, November 12 201312Dr Harold Clenet, EPSL, EPFL 13. OutlineDiversity among the asteroids The electromagnetic spectrum and asteroids characteristics Asteroids families Some physical propertiesTuesday, November 12 2013Where do the asteroids come from? At the beginning of our Solar System From planetesimals to planetary embryos and asteroids Detection of asteroidsAsteroids and society Asteroids as hazards Asteroids as resources13Dr Harold Clenet, EPSL, EPFL 14. The electromagnetic spectrum and asteroids characteristicsMGS TES - 1996MO GRS - 2001Gamma spectroscopyMO THEMIS - 2001 MRO SHARAD - 2005 MEx MARSIS - 2003RadarMGS MOC - 1996Thermal infraredMEx HRSC - 2003MEx OMEGA - 2003MRO CTX & HiRISE - 2005MRO CRISM - 2005Visible optical imagery Visible Near Infrared spectroscopy Tuesday, November 12 201314Dr Harold Clenet, EPSL, EPFL 15. The electromagnetic spectrum and asteroids characteristicsPlancks law relation between the temperature of a body and the energy flux2 hVE ( ,T )2hV 5(ekT1)h = 6.63 10-34 J.s - Plancks constant K = 1.38 10-23 J/s - Boltzmanns constant V = 3.00 108 m/s - light speed - wavelength T - black body temperatureTuesday, November 12 2013Dr Harold Clenet, EPSL, EPFL 16. The electromagnetic spectrum and asteroids characteristicsStefans law Stefans law is the integration of Plancks law for at all the wavelengthsE emis2 hV21 hV50ekStefans constant :5 , 67 . 108Wmd2KTT414T=6000K, Fp=Fi=73.000.000 W.m-2 T=300K, Fp=Fi=459 W.m-2Tuesday, November 12 2013Dr Harold Clenet, EPSL, EPFL 17. The electromagnetic spectrum and asteroids characteristics Wiens law For a given temperature, Wiens law give the wavelength where the enerfy flux is maximalmTCst3000mKT=6000K, max at 0.6 m (middle of the visible) T=300K, max at 10 m (in the thermal infrared)Tuesday, November 12 2013Dr Harold Clenet, EPSL, EPFL 18. The electromagnetic spectrum and asteroids characteristics Black body spectrumTuesday, November 12 2013Dr Harold Clenet, EPSL, EPFL 19. The electromagnetic spectrum and asteroids characteristicsTuesday, November 12 201319Dr Harold Clenet, EPSL, EPFL 20. The electromagnetic spectrum and asteroids characteristics2 process producing absorptionsTuesday, November 12 2013Dr Harold Clenet, EPSL, EPFL 21. Asteroids familiesClassification of asteroids based on their spectral shape Tuesday, November 12 201321Dr Harold Clenet, EPSL, EPFL 22. Asteroids familiesTuesday, November 12 201322Dr Harold Clenet, EPSL, EPFL 23. Asteroids families Tholen classification (source Wikipedia http://en.wikipedia.org/wiki/Asteroid_spectral_types)253 Mathilde 433 Eros21 LutetiaTuesday, November 12 201323Dr Harold Clenet, EPSL, EPFL 24. Asteroids familiesCarbonaceous chondrite (enriched in C + O) Asteroid from C-groupLinks to meteoritesMesosiderite and pallasite (silicates and iron) Asteroids from S-groupIron meteorites Asteroids from M-group Tuesday, November 12 201324Dr Harold Clenet, EPSL, EPFL 25. Asteroids familiesCarbonaceous chondrite (enriched in C + O) Asteroid from C-groupLinks to meteoritesMesosiderite and pallasite (silicates and iron) Asteroids from S-groupIron meteorites Asteroids from M-group Tuesday, November 12 201325Dr Harold Clenet, EPSL, EPFL 26. Asteroids familiesTuesday, November 12 201326Dr Harold Clenet, EPSL, EPFL 27. Some physical properties25143 Itokawa 600 x 300 m4 Vesta 500 km diameterTuesday, November 12 201327Dr Harold Clenet, EPSL, EPFL 28. Some physical propertiesTuesday, November 12 201328Dr Harold Clenet, EPSL, EPFL 29. Some physical propertiesIda and its moon DactylTuesday, November 12 201329Dr Harold Clenet, EPSL, EPFL 30. OutlineDiversity among the asteroids The electromagnetic spectrum and asteroids characteristics Asteroids families Some physical propertiesTuesday, November 12 2013Where do the asteroids come from? At the beginning of our Solar System From planetesimals to planetary embryos and asteroids Detection of asteroidsAsteroids and society Asteroids as hazards Asteroids as resources30Dr Harold Clenet, EPSL, EPFL 31. Asteroids as hazardMercuryThe MoonTuesday, November 12 201331Dr Harold Clenet, EPSL, EPFL 32. Asteroids as hazard65 My ago, end of dinosaursGravity map Tuesday, November 12 201332Dr Harold Clenet, EPSL, EPFL 33. Asteroids as hazardTuesday, November 12 201333Dr Harold Clenet, EPSL, EPFL 34. Asteroids as hazardTunguska (Siberia), 1908Peekskill (New York), 1992Tuesday, November 12 201334Dr Harold Clenet, EPSL, EPFL 35. Asteroids as hazardThe Tcheliabinsk event Tuesday, November 12 201335Dr Harold Clenet, EPSL, EPFL 36. Asteroids as hazardPotentially Hazardous Asteroids (PHAs) > 1400 as early 2013Tuesday, November 12 201336Dr Harold Clenet, EPSL, EPFL 37. Asteroids as resourcesOrion approaching robotic asteroid capture vehicleTuesday, November 12 201337Dr Harold Clenet, EPSL, EPFL 38. Asteroids as resourcesPhoebeOrion approaching robotic asteroid capture vehicleTuesday, November 12 201338Dr Harold Clenet, EPSL, EPFL 39. Asteroids as resourcesEconomic factors Resources (metal/water) Costs of the mission TimingOrion approaching robotic asteroid capture vehicle YOU? Tuesday, November 12 201339Dr Harold Clenet, EPSL, EPFL