Comets,Centaurs and TNOs by elipldoc

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									Comets, Centaurs, & TNOs
  AS3141 Benda Kecil dalam Tata Surya
  Prodi Astronomi 2007/2008
  B. Dermawan
Comets,
Centaurs, &
TNOs
Jewitt (for 2008)
Comets (1)
    Comets (2)
• Short Period Comet (SPC, < 200 y)
     - Halley Family Comet (HFC, 200-20 y)
     - Jupiter Family Comet (JFC, < 20 y)
•   Long Period Comet (LPC, > 200 y)

Tisserand parameter:

Ecliptic: T > 2 ® JFC
Isotropic: T < 2 ® LPC, HFC, Damocloids
    Comets (3)
• Active comet: detectable coma ® volatile & dust
• Inactive comet: no detectable coma
• Dormant comet:
      lost the ability to generate a detectable coma
      in any part of its present orbit
      ® might be reactivated
•   Extinct comet: (= defunc comet?)
      incapable of generating a coma (lost its ices,
      or its ices buried under a nonvolatile crust)
Dormant & Extinct Comets




                   Weissman et al. 2003
            Comet-like Asteroids & Extinct Comets
 Weissman et al. 2003




Weissman et al. 2003
Sun-grazing Comets
     Insitu Explorations
•   Giotto → Halley
•   Deep Space 1 – Borrelly
•   Stardust – Wild2
•   Deep Impact → Tempel 1
Isotopic Abundances
                Hutsemékers 2005
Mainbelt Comets   Hsieh & Jewitt 2006
                Damocloids (1)

Jewitt (2005)

•   Comet-like asteroids whose T £ 2
•   Inactive nuclei of HFC & LPC
•   Have subsequently developed comae
•   About 25% possess retrograde orbits
                       Damocloids (2)
•   The distribution of inclinations is indistinguishable
    from that of the HFC
•   Lack of ultra-red matter




                                                  Jewitt 2005
                               Jewitt 2005
         l : ~4000Å - ~8000Å
Centaurs: Asteroid-like objects with semimajor axes
       between those of Jupiter and Neptune
                                     Johnston 2005
       unusual




              Centaurs

                           From Jupiter to
                          outer solar system
Dotto & Barucci 2004



                                       Albedo                          Centaurs


                                           Colors




                       Delsanti & Jewitt 2006

                                                Dotto & Barucci 2004
           Jewitt (for 2008)




Centaurs




                                   Hainaut &
                                Delsanti 2005




                  Jewitt 2005
(Edgeworth)-Kuiper Belt Objects [(E)KBO]
    Trans-Neptunian Objects (TNOs)
      TNOs: Past Evolution (1)
                                 Tsiganis et al. 2005




Dones et al. 2004
                  TNOs: Past Evolution (2)
                     Levison & Morbidelli 2003




Morbidelli 2004
   TNOs: Non-cometary objects with semimajor
          axes beyond Neptune's orbit

• Plutinos: Near the 2:3 resonance with Neptune. Pluto is the
  largest object near this resonance
• Resonance objects: Other than Plutinos but near resonances
  (4:5, 3:4, 3:5, 4:7, 1:2, 2:5) with Neptune
• Cubewanos: Eccentricities below 0.15 with semimajor axes
  between 41.8 AU and 48 AU (® Classical: cold & hot populations)
• Scattered disk objects (SDOs): Aphelion distances near
  Neptune's orbit and semimajor axes greater than 50 AU
 (+ Extended Scattered or Detached Objects)
• Other TNOs not fitting in the above groups
TNOs: Orbital Distribution
                       Johnston 2005
Number of TNOs (Orbital) Populations




 Delsanti & Jewitt 2006      Lykawka & Mukai 2007
                       Doressoundiram et al. 2007

  TNOs: Spectra (1)
Dotto & Barucci 2004
                 TNOs: Spectra (2)




Doressoundiram et al. 2007
                         TNOs: Sizes (1)
•   Thermal Flux:
    Density:
    Effective temp.:
     Standard Thermal Model (STM, Lebofsky et al. 1989)
     Near-Earth Asteroid Thermal Model (NEATM, Harris 1998)
     Thermo-Physical Model (TPM, Lagerros 1997)

    Bond & Geometric Albedos:


•   Optical Constraints:
                TNOs: Sizes (2)
Johnston 2005
        Size & Albedo of
Unusual Minor Planet C/2002 CE10




                     Sekiguchi et al. 2005
                    Albedo vs Size




Jewitt (for 2008)
                 Albedo & Spectral Gradient
                                              Jewitt 2004
Fernandez et al. 2003
Jewitt et al. 2005
Cruikshank et al. 2006
    Colors (1)

Peixinho 2003




                 Jewitt 2005
Colors (2)
             Doressoundiram & Peixinho 2005
                    Colors (3)




Delsanti & Jewitt 2006
Large TNOs Þ
Dwarf Planets
Large TNOs (Dwarf Planets): Spectra (1)

                 (50000) Quaoar




   Jewitt et al. 2004
Large TNOs (Dwarf Planets): Spectra (2)
                   Pluto & 2003 UB313




 Brown 2006
Small Body Binary (1) Richardson & Walsh 2005




  NEAs       MBAs       Trojan Pluto- TNOs
                              Charon
Small Body Binary (2) Richardson & Walsh 2005




  NEAs       MBAs       Trojan Pluto- TNOs
                              Charon
Dwarf Planet Binary
                      May 2006
Stellar Encounter (1)


     Morbidelli & Levison 2004
   Stellar
Encounter (2)




                Kenyon & Bromley 2004
   Stellar
Encounter (2)




    Kenyon & Bromley 2004
   Stellar
Encounter (2)




    Kenyon & Bromley 2004

								
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