Comets, Centaurs, & TNOs AS3141 Benda Kecil dalam Tata Surya Prodi Astronomi 2006/2007 B. Dermawan AS3141 Benda Kecil dalam Tata Surya Prodi Astronomi 2006/2007 B. Dermawan

Benda Kecil Tata Surya Asteroids (MBAs, NEAs) Comets (periode pendek, panjang; ekliptik, isotropik) Meteoroids (  meteors, meteorites) (Edgeworth)-Kuiper Belt Objects or Trans- Neptunian Objects Centaurs (Jupiter-Neptune), Damocloids Hipotesis: vulcanoids, ‘awan’ Oort Asteroids (MBAs, NEAs) Comets (periode pendek, panjang; ekliptik, isotropik) Meteoroids (  meteors, meteorites) (Edgeworth)-Kuiper Belt Objects or Trans- Neptunian Objects Centaurs (Jupiter-Neptune), Damocloids Hipotesis: vulcanoids, ‘awan’ Oort

Comets, Centaurs, Damocloids, & TNOs

Comets (1)

Comets (2) Periode Pendek (SPC, < 200 th) - Halley Type Comets (HTC, th) - Jupiter Family Comets (JFC, < 20 th) Periode Panjang (LPC, > 200 th) Periode Pendek (SPC, < 200 th) - Halley Type Comets (HTC, th) - Jupiter Family Comets (JFC, < 20 th) Periode Panjang (LPC, > 200 th) Ekliptik: T > 2  JFC Isotropik: T < 2  LPC, HTC, Damocloids Ekliptik: T > 2  JFC Isotropik: T < 2  LPC, HTC, Damocloids Parameter Tisserand:

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: incapable of generating a coma (lost its ices, or its ices buried under a nonvolatile crust) 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: 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

Sun-grazing Comets

Insitu Explorations Giotto → Halley Deep Space 1 – Borrelly Stardust – Wild2 Deep Impact → Temple 1 Giotto → Halley Deep Space 1 – Borrelly Stardust – Wild2 Deep Impact → Temple 1

Isotopic Abundances Hutsemékers 2005

Centaurs: Asteroid-like objects with semimajor axes between those of Jupiter and Neptune Centaurs unusual Johnston 2005

Centaurs Albedo Colors Dotto & Barucci 2004

Damocloids (1) Jewitt (2004) Comet-like asteroids whose T  2 Inactive nuclei of HTC & LPC Have subsequently developed comae About 25% possess retrograde orbits Jewitt (2004) Comet-like asteroids whose T  2 Inactive nuclei of HTC & LPC Have subsequently developed comae About 25% possess retrograde orbits

Damocloids (2) The distribution of inclinations is indistinguishable from that of the HFC Lack ultrared matter The distribution of inclinations is indistinguishable from that of the HFC Lack ultrared matter : ~4000Å - ~8000Å Jewitt 2004

(Edgeworth)-Kuiper Belt Objects [(E)KBO] Trans-Neptunian Objects (TNOs)

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. Scattered disk objects (SDOs): Aphelion distances near Neptune's orbit and semimajor axes greater than 50 AU. Other TNOs not fitting in the above groups. 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. Scattered disk objects (SDOs): Aphelion distances near Neptune's orbit and semimajor axes greater than 50 AU. Other TNOs not fitting in the above groups.

TNOs: Orbital Dist. (1) Johnston 2005

TNOs: Orbital Dist. (2) Lykawka & Mukai 2005

TNOs: Orbital Dist. (3) Jewitt 2004

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 Albedo & Geometric Albedo: Optical Constraints:

Size & Albedo of Unusual Minor Planet C/2002 CE 10 Sekiguchi et al. 2005

TNOs: Sizes (2) Johnston 2005

TNOs: Spectrum Dotto & Barucci 2004

TNOs: Binary (1) Richardson & Walsh 2005 NEAsMBAs Trojan Pluto- Charon TNOs

TNOs: Binary (2) Richardson & Walsh 2005 NEAsMBAs Trojan Pluto- Charon TNOs

Albedo & Spectral Gradient Jewitt 2004 Dotto & Barucci 2004

Albedo vs Diameter Lykawka & Mukai 2005

Colors (1) Jewitt 2004 Peixinho 2003

Colors (2) Doressoundiram & Peixinho 2005

Atmospheres? Lykawka & Mukai 2005

Stellar Encounter (1) Kenyon & Bromley 2004

Stellar Encounter (2) Kenyon & Bromley 2004

Stellar Encounter (3) Kenyon & Bromley 2004