3- to 14-μm Spectroscopy of Comet C/1999 T1 (McNaught–Hartley)

✍ Scribed by David K. Lynch; Ray W. Russell; Michael L. Sitko

• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 96 KB
• Volume: 159
• Category: Article
• ISSN: 0019-1035
• DOI: 10.1006/icar.2002.6882

✦ Synopsis

using the broadband array spectrograph system on the IRTF. The spectrum showed a silicate emission feature extending about 20% above the continuum. Two emission features at 10.3 and 11.2 µm appeared above the silicate band, the latter seemingly indicative of crystalline olivine. The 10.3-µm feature is only a 1-2 sigma detection but if real could indicate the presence of hydrated silicates. The color temperature at 8-13 µm was 260 ± 10 K, approximately 6% above the blackbody radiative equilibrium temperature of 235 K. The magnitude at [N] was 3.13 ± 0.02. On the second night, the comet had brightened slightly ([N] = 2.98 ± 0.02) and the two prominent emission features were absent, although the silicate emission feature maintained its trapezoidal shape with shoulders at 9.5 and 11.2 µm.