title: The activity and size of the nucleus of comet Hale-Bopp (C/1995 O1) [see comment].
abstract: Analysis of Hubble Space Telescope (HST) images of comet Hale-Bopp (C/1995 O1) suggests that the effective diameter of the nucleus is between 27 to 42 kilometers, which is at least three times larger than that of comet P/Halley. The International Ultraviolet Explorer and HST spectra showed emissions from OH (a tracer of H2O) and CS (a tracer of CS2) starting in April 1996, and from the CO Cameron system (which primarily traces CO2) starting in June 1996. The variation of the H2O production rate with heliocentric distance was consistent with sublimation of an icy body near its subsolar point. The heliocentric variation in the production rates of CS2 and dust was different from that of H2O, which implies that H2O sublimation did not control the CS2 or dust production during these observations.
authors.affiliation: Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA.
authors.forename: H A
authors.initials: HA
authors.lastname: Weaver
authors.forename: P D
authors.initials: PD
authors.lastname: Feldman
authors.forename: M F
authors.initials: MF
authors.lastname: A'Hearn
authors.forename: C
authors.initials: C
authors.lastname: Arpigny
authors.forename: J C
authors.initials: JC
authors.lastname: Brandt
authors.forename: M C
authors.initials: MC
authors.lastname: Festou
authors.forename: M
authors.initials: M
authors.lastname: Haken
authors.forename: J B
authors.initials: JB
authors.lastname: McPhate
authors.forename: S A
authors.initials: SA
authors.lastname: Stern
authors.forename: G P
authors.initials: GP
authors.lastname: Tozzi
mesh_terms: D002245:Carbon Dioxide / Q000032:analysis; D002246:Carbon Disulfide / Q000032:analysis; D019443:Cosmic Dust; D019110:Meteoroids; D013057:Spectrum Analysis; D014867:Water
chemical_list: D019443:Cosmic Dust; D014867:Water; D002245:Carbon Dioxide; D002246:Carbon Disulfide