Spectral and spin measurement of two small and fast-rotating near-Earth asteroids

Autor: Richard P. Binzel, David Polishook, W. Golisch, Francesca E. DeMeo, Amanda A. S. Gulbis, S. J. Bus, M. Lockhart
Přispěvatelé: Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences, Polishook, David, Binzel, Richard P., Lockhart, Matthew, DeMeo, Francesca E., Gulbis, Amanda A. S.
Rok vydání: 2012
Předmět:
Zdroj: arXiv
ISSN: 0019-1035
DOI: 10.1016/j.icarus.2012.08.013
Popis: In May 2012 two asteroids made near-miss "grazing" passes at distances of a few Earth-radii: 2012 KP24 passed at nine Earth-radii and 2012 KT42 at only three Earth-radii. The latter passed inside the orbital distance of geosynchronous satellites. From spectral and imaging measurements using NASA's 3-m Infrared Telescope Facility (IRTF), we deduce taxonomic, rotational, and physical properties. Their spectral characteristics are somewhat atypical among near-Earth asteroids: C-complex for 2012 KP24 and B-type for 2012 KT42, from which we interpret the albedos of both asteroids to be between 0.10 and 0.15 and effective diameters of 20+-2 and 6+-1 meters, respectively. Among B-type asteroids, the spectrum of 2012 KT42 is most similar to 3200 Phaethon and 4015 Wilson-Harrington. Not only are these among the smallest asteroids spectrally measured, we also find they are among the fastest-spinning: 2012 KP24 completes a rotation in 2.5008+-0.0006 minutes and 2012 KT42 rotates in 3.634+-0.001 minutes.
4 pages, 3 figures, accepted for publication in Icarus
Databáze: OpenAIRE
Externí odkaz: