Bibcode
Ziffer, J.; Campins, H.; Licandro, J.; Fernandez, Y. R.; Bus, S.
Referencia bibliográfica
American Astronomical Society, DPS meeting #37, #15.29; Bulletin of the American Astronomical Society, Vol. 37, p.644
Advertised on:
8
2005
Número de citas
0
Número de citas referidas
0
Descripción
We present near-infrared reflectance spectra of two asteroids with low
Tisserand invariant, 2906 Caltech and 1373 Cincinnati. The Tisserand
invariant is a commonly used dynamical discriminator, with values less
than 3 considered suggestive of cometary origin. Asteroids Caltech and
Cincinnati have Tisserand invariant values of 2.97 and 2.72
respectively. However, other factors, including their mean orbital
intersection distance (MOID) with Jupiter, suggest neither asteroid has
a cometary origin. Our spectra covered the 0.8-2.4 micron region and
were obtained on UT 22.23 and 23.60 October 2004, using the SpeX
instrument at NASA's infrared telescope facility (IRTF) on Mauna Kea.
Our reflectance spectra of Caltech and Cincinnati, normalized at 1.22
microns, yield slopes with 17 and 27 percent change in reflectance per
micron respectively and display no strong absorption features. The
observed red slopes and weak or absent spectral features in the
near-infrared are consistent with both the spectra of comet nuclei and
of primitive asteroids. We present a detailed spectral comparison of
these two asteroids with other comet-asteroid transition objects that
are more likely to have a cometary origin, such as 28 P/Neujmin 1
(Licandro et al., 2002), C/2001 OG108 (Abell et al., 2005), 162P/Siding
Spring (2004 TU12) and 944 Hidalgo (Campins et al., 2005).
References:
Abell et al., 2005. Physical Characteristics of Comet Nucleus C/2001
OG108 (LONEOS). Icarus (in press).
Campins et al., 2005. Surface Characteristics of Comet-Asteroid
Transition Objects 944 Hidalgo and 162P/Siding Spring (2004 TU12).
Asteroids Comets Meteors (abstract).
Licandro et al., 2002. The Surface of Cometary Nuclei Related Minor Icy
Bodies. Earth, Moon, and Planets 90, 495-496.