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Near-Infrared Spectra of Centaurs and Kuiper Belt Objects
We present here an extensive survey of near-infrared (NIR) spectra ofKuiper belt objects (KBOs) and Centaurs taken with the Keck I Telescope.We find that most spectra in our sample are well characterized by acombination of water ice and a featureless continuum. A comparativeanalysis reveals that the NIR spectral properties have littlecorrelation to the visible colors or albedo, with the exception of thefragment KBOs produced from the giant impact on 2003 EL61. The resultssuggest that the surface composition of KBOs is heterogeneous, thoughthe exposure of water ice may be controlled by geophysical processes.The Centaurs also display diverse spectral properties, but the source ofthe variability remains unclear. The results for both the KBOs and theCentaurs point to inherent heterogeneity in either the processes actingon these objects or materials from which they formed.
| UBV(RI)C photometric monitoring of Orion population stars in the Southern Hemisphere
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| UVBY observations of A, F, G and K field stars
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Osservazione e dati astrometrici
| Costellazione: | Ofiuco |
| Ascensione retta: | 16h50m03.66s |
| Declinazione: | -15°25'34.4" |
| Magnitudine apparente: | 8.821 |
| Distanza: | 72.411 parsec |
| Moto proprio RA: | 1.2 |
| Moto proprio Dec: | 26.6 |
| B-T magnitude: | 9.505 |
| V-T magnitude: | 8.878 |
Cataloghi e designazioni:
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