The infrared spectrum of comet C / 1995 O 1 ( Hale - Bopp ) at 4 . 6 AU from the Sun ?
نویسندگان
چکیده
Comet C/1995 O1 (Hale-Bopp) was observed on 27 April 1996 with the ISOPHOT instrument of ISO when it was at 4.6 AU from the Sun. The 2.5–12 m spectrum was recorded at low resolution. We present here the preliminary results of this observation. The 2.5–5 m spectrum shows emission in the CO2 3 band. The CO2 production rate is about 1:3 1028 s 1. The 6–12 m spectrum shows thermal emission at a colour temperature of 162 K (6–8 m range) and a strong silicate band around 10 m, with a narrow feature at 11.2 m indicative of crystalline silicates.
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