Letter to the Editor Evidence for water ice and estimate of dust production rate in comet Hale-Bopp at 2.9 AU from the Sun
نویسنده
چکیده
We report observational evidence for water ice in comet C/1995 O1 (Hale-Bopp) when it was at 2.9 AU from the Sun, from emission features at 44 and 65 μm, and possibly an absorption feature at 3.1 μm, observed with ISO/LWS and PHT. We find that icy grains have mean radii of 15 μm within a factor of 2, lifetimes of ∼ 2 days, a temperature of ∼ 153 K, and a total mass of ∼2×109 kg. From investigation of the continuum spectrum at 43–195 μm, we also infer a production rate of large particles (∼ 100 μm) dust of about 4×104 kg s−1.
منابع مشابه
Water Production and Release in Comet C/1995 O1 Hale–Bopp
Water (H2O) was detected in Comet C/1995 O1 Hale–Bopp on 10 dates between UT January 21.8 and May 1.2, 1997, using highresolution infrared spectroscopy. This is the first study of the heliocentric dependence of water released from a comet using direct detection of H2O itself. Production rates and rotational temperatures were measured, and the derived heliocentric dependence for the water produc...
متن کاملBroadband infrared photometry of comet Hale-Bopp with ISOPHOT
Comet Hale-Bopp was observed five times with ISOPHOT, the photometer on board ESA’s Infrared Space Observatory (ISO) between 4.6 and 2.8 AU. Each time, broadband photometry was performed using 4 different detectors, 5 apertures and 10 filters covering the range between 3.6 and 170 μm. Background observations were performed with identical instrument settings at the same positions on the sky seve...
متن کاملIrregular Particles in Comet C/1995 O1 Hale-bopp Inferred from Its Mid-infrared Spectrum
An analysis of the Infrared Space Observatory (ISO) infrared spectra of comet C/1995 O1 Hale-Bopp has been conducted. The particles in the coma are assumed to be irregular aggregates that are built by a diffusionlimited aggregation (DLA) procedure and are composed of olivine, both amorphous and crystalline, and glassy carbon. To simulate the morphological structure of the interstellar dust, the...
متن کاملLetter to the Editor Radio detection of ammonia in comet Hale-Bopp
Radio emission from ammonia, a suspected parent molecule in comets, was detected from comet Hale-Bopp near its perihelion passage with the 100-m Effelsberg Radio Telescope. Signals from the five lowest metastable inversion transitions of NH3 were obtained to derive a rotational temperature of 104±30 K, assumed to be representative of the kinetic temperature in the comet’s inner coma (R < 5000 k...
متن کاملFrom Interstellar Dust to Comets: Infrared Emission from Comet Hale-bopp (c/1995 O1)
The 3–20 mm IR thermal emission spectrum of comet Hale-Bopp (C/1995 O1) at a heliocentric distance of AU has been calculated using fluffy aggregates of silicate core–organic refractory mantle interstellar r 5 1.15 h dust as the comet dust model. The principal dust properties, similar to those obtained for other comets, provide good fits to the observation. Our results are significantly differen...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 1998