Spectral observations in the 2.5-12 μm range of comet 103P/Hartley 2 were performed on 1 Jan. 1998 by the ISOPHOT instrument, on board the Infrared Space Observatory. The obtained spectrum evidences intense bands at 2.66 and 4.26 μm, attributable to H 2O and CO 2, respectively. The derived molecular production rates are Q(H 2O) = (3.1 ± 0.2) à 10 28 molec. s -1 and Q(CO 2) = (2.5 ± 0.3) à 10 27 molec. s -1. This leads to a CO 2/H 2O abundance ratio of ⼠8%, showing that P/Hartley 2 is a relatively CO 2 abundant comet, with respect to IP/Halley and several other comets. A feature has been detected at 3.69 μm, whose attribution is rather puzzling. The long wavelength part of the spectrum is well fitted by a black-body profile at 285 K colour temperature. No significant silicate emission feature around 10 μm is observed, within observation errors.
Infrared spectral observations of comet 103P/Hartley 2 by ISOPHOT
COLANGELI, Luigi;EPIFANI, Elena;BUSSOLETTI, Ezio;FULLE, Marco;MENNELLA, Vito;PALUMBO, Pasquale;ROTUNDI, Alessandra
1999-01-01
Abstract
Spectral observations in the 2.5-12 μm range of comet 103P/Hartley 2 were performed on 1 Jan. 1998 by the ISOPHOT instrument, on board the Infrared Space Observatory. The obtained spectrum evidences intense bands at 2.66 and 4.26 μm, attributable to H 2O and CO 2, respectively. The derived molecular production rates are Q(H 2O) = (3.1 ± 0.2) à 10 28 molec. s -1 and Q(CO 2) = (2.5 ± 0.3) à 10 27 molec. s -1. This leads to a CO 2/H 2O abundance ratio of ⼠8%, showing that P/Hartley 2 is a relatively CO 2 abundant comet, with respect to IP/Halley and several other comets. A feature has been detected at 3.69 μm, whose attribution is rather puzzling. The long wavelength part of the spectrum is well fitted by a black-body profile at 285 K colour temperature. No significant silicate emission feature around 10 μm is observed, within observation errors.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.