Substantial outgassing of CO from comet Hale–Bopp at large heliocentric distance

  title={Substantial outgassing of CO from comet Hale–Bopp at large heliocentric distance},
  author={Nicolas Biver and Heike Rauer and Didier Despois and Raphael Moreno and Gabriel Paubert and Dominique Bockel{\'e}e-Morvan and Pierre Colom and Jacques Crovisier and {\'E}ric G{\'e}rard and Laurent Jorda},
WHEN comet C/1995 Ol (Hale–Bopp) was discovered1, at a distance of seven astronomical units from the Sun, it was more than one hundred times brighter than comet Halley at the same distance. A comet's brightness is derived from the reflection of sunlight from dust grains driven away from the nucleus by the sublimation of volatile ices. Near the Sun, sublimation of water ice (a main constituent of comet nuclei) is the source of cometary activity; but at its current heliocentric distance, Hale… 

On the Outgassing Profile of Comet Hale-Bopp

When Comet Hale-Bopp was first discovered at a heliocentric distance of ~7.2 AU, its activity appeared to be controlled by the outgassing of the highly volatile CO molecule. Its gas production

CO in distantly active comets

Activity of most comets near the Sun is dominated by sublimation of frozen water, the most abundant ice in comets. Some comets, however, are active well beyond the water-ice sublimation limit of ~3

Long-term Evolution of the Outgassing of Comet Hale-Bopp From Radio Observations

C/1995 O1 (Hale-Bopp) has been observed on a regular basis since August 1995 at millimetre and submillimetre wavelengths using IRAM, JCMT, CSO and SEST radio telescopes. The production rates of eight

Optical Observations of Comet Hale-Bopp (C/1995 O1) at Large Heliocentric Distances Before Perihelion

The production rate of the CN radical to its proposed parent, HCN, shows no evidence for the need of a major additional source for CN in Hale-Bopp at large heliocentric distances, and the observed band intensities of the NH2 radical and the H2O+ ion cannot be explained by existing models of fluorescence excitation.

C/1995 O1 (Hale-Bopp): Gas Production Curves And Their Interpretation

The discovery of C/1995 O1 (Hale-Bopp) at 7 AU from the Sun provided the first opportunity to follow the activity of a bright comet over a large range of heliocentric distances rh. Production rates

Evolution of the Outgassing of Comet Hale-Bopp (C/1995 O1) from Radio Observations

Spectra obtained from ground-based radio telescopes show the progressive release of CO, CH3OH, HCN, H2O (from OH), H2S, CS, H2CO, CH3CN, and HNC as comet Hale-Bopp (C/1995 O1) approached the sun from

CO and Other Volatiles in Distantly Active Comets

The activity of most comets near the Sun is dominated by the sublimation of frozen water, the most abundant ice in comets. Some comets, however, are active well beyond the water-ice sublimation limit

The Activity and Size of the Nucleus of Comet Hale-Bopp (C/1995 O1)

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

Radio Line Observations Of Molecular And Isotopic Species In Comet C/1995 O1 (Hale-Bopp)

We present here a review of the radio observations of the remarkable comet Hale-Bopp C/1995 O1 in which most major radio astronomical facilities have been involved. These observations started in



Coma formation driven by carbon monoxide release from comet Schwassmann–Wachmann 1

DISTANT comets are sometimes observed to undergo outbursts of activity that generate a surrounding coma, but the cause of this activity is not known1,2. Whereas such outbursts in near-Sun comets are

Dust from short-period comet P/Schwassmann–Wachmann 1 and replenishment of the interplanetary dust cloud

IF the current abundance of interplanetary dust is representative of its long-term value1, there must be a source of dust replenishing the ∼107 g s–1 (mostly in the form of particles of 10–4 to 1 g)

The persistent coma of Comet P/Schwassmann-Wachmann 1

Time-series photometry of Comet P/Schwassmann-Wachmann 1 in both 1987 and 1988 shows that this comet is continually active despite its large heliocentric distance. The observed activity, upon which

Carbon Monoxide Outgassing from Comet P/Schwassmann-Wachmann 1

Abstract We observed the J (2-1) and (1-0) lines of CO in Comet P/Schwassmann-Wachmann 1 with high spectral resolution at four different epochs. The line profile is dominated by a very narrow (0.14

Comet Bowell (1980b)

Optical filter photometry, and optical and ultraviolet spectrophotometry data collected between November 1980 and June 1982 of Comet Bowell are presented. It was determined that Comet Bowell began

Molecular Abundances in Comets

The molecular composition of cometary volatiles is a basic information on the nature of comets and a clue to their formation mechanisms. It is only recently that direct identifications of cometary