Learn More
Comet Hale-Bopp (C/1995 O1) was observed at wavelengths from 2.4 to 195 micrometers with the Infrared Space Observatory when the comet was about 2.9 astronomical units (AU) from the sun. The main observed volatiles that sublimated from the nucleus ices were water, carbon monoxide, and carbon dioxide in a ratio (by number) of 10:6:2. These species are also(More)
Along Ulysses' path from Jupiter to the south ecliptic pole, the onboard dust detector measured a dust impact rate that varied slowly from 0.2 to 0.5 impacts per day. The dominant component of the dust flux arrived from an ecliptic latitude and longitude of 100 + 10 degrees and 280 degrees +/- 30 degrees which indicates an interstellar origin. An additional(More)
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(More)
Infrared spectral properties of silicate grains in interplanetary dust particles (IDPs) were compared with those of astronomical silicates. The approximately 10-micrometer silicon-oxygen stretch bands of IDPs containing enstatite (MgSiO3), forsterite (Mg2SiO4), and glass with embedded metal and sulfides (GEMS) exhibit fine structure and bandwidths similar(More)
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 CO 2 3 band. The CO 2 production rate is about 1:3 10 28 s 1. The 6–12 m(More)
  • E Grun, M S Hanner, S Peschke, B Muller, T Boehnhardt, H Brooke +41 others
  • 2016
Copyright and Moral Rights for the articles on this site are retained by the individual authors and/or other copyright owners. For more information on Open Research Online's data policy on reuse of materials please consult the policies page. Abstract. Comet Hale-Bopp was observed five times with ISOPHOT, the photometer on board ESA's Infrared Space(More)
  • E Grün, S B Peschke, M Stickel, T Müller, H Krüger, H Böhnhardt +17 others
  • 1998
Comet Hale-Bopp was observed five times with ISOPHOT, the photometer on board the Infrared Space Observatory (ISO). Each time broadband pho-tometry was performed using 4 different detectors, 5 apertures and, 10 filters covering the range between 3.6 to 175 µm. Calibration measurements using the internal Fine Calibration Source were done together with each(More)
Thermal infrared (IR) imaging and spectroscopy of comet Hale-Bopp (C/1995 O1) during June, August, and September 1996 traced the development of the dust coma several months before perihelion. Images revealed nightly variations in the brightness of the inner coma from 1 to 12 June that were correlated with the appearance of a northward-pointing jet. The(More)
Submicrometer- to micrometer-sized particles were recorded by the Ulysses dust detector within 40 days of the Jupiter flyby. Nine impacts were recorded within 50 Jupiter radii with most of them recorded after closest approach. Three of these impacts are consistent with particles on prograde orbits around Jupiter and the rest are believed to have resulted(More)