The molecular composition of Comet C/2007 W1 (Boattini): Evidence of a peculiar outgassing and a rich chemistry

G. L. Villanueva, M. J. Mumma, M. A. DiSanti, B. P. Bonev, E. L. Gibb, K. Magee-Sauer, G. A. Blake, C. Salyk

Research output: Contribution to journalArticle

49 Citations (Scopus)

Abstract

We measured the chemical composition of Comet C/2007 W1 (Boattini) using the long-slit echelle grating spectrograph at Keck-2 (NIRSPEC) on 2008 July 9 and 10. We sampled 11 volatile species (H2O, OH*, C2H6, CH3OH, H2CO, CH4, HCN, C2H2, NH3, NH2, and CO), and retrieved three important cosmogonic indicators: the ortho-para ratios of H2O and CH4, and an upper-limit for the D/H ratio in water. The abundance ratios of almost all trace volatiles (relative to water) are among the highest ever observed in a comet. The comet also revealed a complex outgassing pattern, with some volatiles (the polar species H2O and CH3OH) presenting very asymmetric spatial profiles (extended in the anti-sunward hemisphere), while others (e.g., C2H6 and HCN) showed particularly symmetric profiles. We present emission profiles measured along the Sun-comet line for all observed volatiles, and discuss different production scenarios needed to explain them. We interpret the emission profiles in terms of release from two distinct moieties of ice, the first being clumps of mixed ice and dust released from the nucleus into the sunward hemisphere. The second moiety considered is very small grains of nearly pure polar ice (water and methanol, without dark material or apolar volatiles). Such grains would sublimate only very slowly, and could be swept into the anti-sunward hemisphere by radiation pressure and solar-actuated non-gravitational jet forces, thus providing an extended source in the anti-sunward hemisphere.

Original languageEnglish (US)
Pages (from-to)227-240
Number of pages14
JournalIcarus
Volume216
Issue number1
DOIs
StatePublished - Nov 1 2011

Fingerprint

outgassing
hemispheres
comets
comet
chemistry
ice
profiles
echelle gratings
sublimate
water
radiation pressure
clumps
spectrographs
slits
methanol
chemical composition
sun
methyl alcohol
dust
nuclei

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Villanueva, G. L., Mumma, M. J., DiSanti, M. A., Bonev, B. P., Gibb, E. L., Magee-Sauer, K., ... Salyk, C. (2011). The molecular composition of Comet C/2007 W1 (Boattini): Evidence of a peculiar outgassing and a rich chemistry. Icarus, 216(1), 227-240. https://doi.org/10.1016/j.icarus.2011.08.024
Villanueva, G. L. ; Mumma, M. J. ; DiSanti, M. A. ; Bonev, B. P. ; Gibb, E. L. ; Magee-Sauer, K. ; Blake, G. A. ; Salyk, C. / The molecular composition of Comet C/2007 W1 (Boattini) : Evidence of a peculiar outgassing and a rich chemistry. In: Icarus. 2011 ; Vol. 216, No. 1. pp. 227-240.
@article{b836d97cfdc94651b1cfb28b1d465e02,
title = "The molecular composition of Comet C/2007 W1 (Boattini): Evidence of a peculiar outgassing and a rich chemistry",
abstract = "We measured the chemical composition of Comet C/2007 W1 (Boattini) using the long-slit echelle grating spectrograph at Keck-2 (NIRSPEC) on 2008 July 9 and 10. We sampled 11 volatile species (H2O, OH*, C2H6, CH3OH, H2CO, CH4, HCN, C2H2, NH3, NH2, and CO), and retrieved three important cosmogonic indicators: the ortho-para ratios of H2O and CH4, and an upper-limit for the D/H ratio in water. The abundance ratios of almost all trace volatiles (relative to water) are among the highest ever observed in a comet. The comet also revealed a complex outgassing pattern, with some volatiles (the polar species H2O and CH3OH) presenting very asymmetric spatial profiles (extended in the anti-sunward hemisphere), while others (e.g., C2H6 and HCN) showed particularly symmetric profiles. We present emission profiles measured along the Sun-comet line for all observed volatiles, and discuss different production scenarios needed to explain them. We interpret the emission profiles in terms of release from two distinct moieties of ice, the first being clumps of mixed ice and dust released from the nucleus into the sunward hemisphere. The second moiety considered is very small grains of nearly pure polar ice (water and methanol, without dark material or apolar volatiles). Such grains would sublimate only very slowly, and could be swept into the anti-sunward hemisphere by radiation pressure and solar-actuated non-gravitational jet forces, thus providing an extended source in the anti-sunward hemisphere.",
author = "Villanueva, {G. L.} and Mumma, {M. J.} and DiSanti, {M. A.} and Bonev, {B. P.} and Gibb, {E. L.} and K. Magee-Sauer and Blake, {G. A.} and C. Salyk",
year = "2011",
month = "11",
day = "1",
doi = "10.1016/j.icarus.2011.08.024",
language = "English (US)",
volume = "216",
pages = "227--240",
journal = "Icarus",
issn = "0019-1035",
publisher = "Academic Press Inc.",
number = "1",

}

Villanueva, GL, Mumma, MJ, DiSanti, MA, Bonev, BP, Gibb, EL, Magee-Sauer, K, Blake, GA & Salyk, C 2011, 'The molecular composition of Comet C/2007 W1 (Boattini): Evidence of a peculiar outgassing and a rich chemistry', Icarus, vol. 216, no. 1, pp. 227-240. https://doi.org/10.1016/j.icarus.2011.08.024

The molecular composition of Comet C/2007 W1 (Boattini) : Evidence of a peculiar outgassing and a rich chemistry. / Villanueva, G. L.; Mumma, M. J.; DiSanti, M. A.; Bonev, B. P.; Gibb, E. L.; Magee-Sauer, K.; Blake, G. A.; Salyk, C.

In: Icarus, Vol. 216, No. 1, 01.11.2011, p. 227-240.

Research output: Contribution to journalArticle

TY - JOUR

T1 - The molecular composition of Comet C/2007 W1 (Boattini)

T2 - Evidence of a peculiar outgassing and a rich chemistry

AU - Villanueva, G. L.

AU - Mumma, M. J.

AU - DiSanti, M. A.

AU - Bonev, B. P.

AU - Gibb, E. L.

AU - Magee-Sauer, K.

AU - Blake, G. A.

AU - Salyk, C.

PY - 2011/11/1

Y1 - 2011/11/1

N2 - We measured the chemical composition of Comet C/2007 W1 (Boattini) using the long-slit echelle grating spectrograph at Keck-2 (NIRSPEC) on 2008 July 9 and 10. We sampled 11 volatile species (H2O, OH*, C2H6, CH3OH, H2CO, CH4, HCN, C2H2, NH3, NH2, and CO), and retrieved three important cosmogonic indicators: the ortho-para ratios of H2O and CH4, and an upper-limit for the D/H ratio in water. The abundance ratios of almost all trace volatiles (relative to water) are among the highest ever observed in a comet. The comet also revealed a complex outgassing pattern, with some volatiles (the polar species H2O and CH3OH) presenting very asymmetric spatial profiles (extended in the anti-sunward hemisphere), while others (e.g., C2H6 and HCN) showed particularly symmetric profiles. We present emission profiles measured along the Sun-comet line for all observed volatiles, and discuss different production scenarios needed to explain them. We interpret the emission profiles in terms of release from two distinct moieties of ice, the first being clumps of mixed ice and dust released from the nucleus into the sunward hemisphere. The second moiety considered is very small grains of nearly pure polar ice (water and methanol, without dark material or apolar volatiles). Such grains would sublimate only very slowly, and could be swept into the anti-sunward hemisphere by radiation pressure and solar-actuated non-gravitational jet forces, thus providing an extended source in the anti-sunward hemisphere.

AB - We measured the chemical composition of Comet C/2007 W1 (Boattini) using the long-slit echelle grating spectrograph at Keck-2 (NIRSPEC) on 2008 July 9 and 10. We sampled 11 volatile species (H2O, OH*, C2H6, CH3OH, H2CO, CH4, HCN, C2H2, NH3, NH2, and CO), and retrieved three important cosmogonic indicators: the ortho-para ratios of H2O and CH4, and an upper-limit for the D/H ratio in water. The abundance ratios of almost all trace volatiles (relative to water) are among the highest ever observed in a comet. The comet also revealed a complex outgassing pattern, with some volatiles (the polar species H2O and CH3OH) presenting very asymmetric spatial profiles (extended in the anti-sunward hemisphere), while others (e.g., C2H6 and HCN) showed particularly symmetric profiles. We present emission profiles measured along the Sun-comet line for all observed volatiles, and discuss different production scenarios needed to explain them. We interpret the emission profiles in terms of release from two distinct moieties of ice, the first being clumps of mixed ice and dust released from the nucleus into the sunward hemisphere. The second moiety considered is very small grains of nearly pure polar ice (water and methanol, without dark material or apolar volatiles). Such grains would sublimate only very slowly, and could be swept into the anti-sunward hemisphere by radiation pressure and solar-actuated non-gravitational jet forces, thus providing an extended source in the anti-sunward hemisphere.

UR - http://www.scopus.com/inward/record.url?scp=80053520933&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=80053520933&partnerID=8YFLogxK

U2 - 10.1016/j.icarus.2011.08.024

DO - 10.1016/j.icarus.2011.08.024

M3 - Article

AN - SCOPUS:80053520933

VL - 216

SP - 227

EP - 240

JO - Icarus

JF - Icarus

SN - 0019-1035

IS - 1

ER -