[en] 176P/LINEAR is a member of the new cometary class known as main-belt comets (MBCs). It displayed cometary activity shortly during its 2005 perihelion passage, which may be driven by the sublimation of subsurface ices. We have therefore searched for emission of the H[SUB]2[/SUB]O 1[SUB]10[/SUB]-1[SUB]01[/SUB] ground state rotational line at 557 GHz toward 176P/LINEAR with the Heterodyne Instrument for the Far Infrared (HIFI) onboard the Herschel Space Observatory on UT 8.78 August 2011, about 40 days after its most recent perihelion passage, when the object was at a heliocentric distance of 2.58 AU. No H[SUB]2[/SUB]O line emission was detected in our observations, from which we derive sensitive 3-σ upper limits for the water production rate and column density of <4 × 10[SUP]25[/SUP] mol s[SUP]-1[/SUP] and of <3 × 10[SUP]10[/SUP] cm[SUP]-2[/SUP], respectively. From the peak brightness measured during the object's active period in 2005, this upper limit is lower than predicted by the relation between production rates and visual magnitudes observed for a sample of comets at this heliocentric distance. Thus, 176P/LINEAR was most likely less active at the time of our observation than during its previous perihelion passage. The retrieved upper limit is lower than most values derived for the H[SUB]2[/SUB]O production rate from the spectroscopic search for CN emission in MBCs. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
de Val-Borro, M.; Max Planck Institute for Solar System Research, Max-Planck-Str. 2, 37191, Katlenburg-Lindau, Germany
Rezac, L.; Max Planck Institute for Solar System Research, Max-Planck-Str. 2, 37191, Katlenburg-Lindau, Germany
Hartogh, P.; Max Planck Institute for Solar System Research, Max-Planck-Str. 2, 37191, Katlenburg-Lindau, Germany
Biver, N.; LESIA, Observatoire de Paris, CNRS, UPMC, Université Paris-Diderot, 5 place Jules Janssen, 92195, Meudon, France
Bockelée-Morvan, D.; LESIA, Observatoire de Paris, CNRS, UPMC, Université Paris-Diderot, 5 place Jules Janssen, 92195, Meudon, France
Crovisier, J.; LESIA, Observatoire de Paris, CNRS, UPMC, Université Paris-Diderot, 5 place Jules Janssen, 92195, Meudon, France
Küppers, M.; Rosetta Science Operations Centre, ESAC, European Space Agency, 28691 Villanueva de la Cañada, Madrid, Spain
Lis, D. C.; California Institute of Technology, Pasadena, CA, 91125, USA
Szutowicz, S.; Space Research Centre, Polish Academy of Sciences, Warsaw, Poland
Blake, G. A.; California Institute of Technology, Pasadena, CA, 91125, USA
Emprechtinger, M.; California Institute of Technology, Pasadena, CA, 91125, USA
Jarchow, C.; Max Planck Institute for Solar System Research, Max-Planck-Str. 2, 37191, Katlenburg-Lindau, Germany
Jehin, Emmanuel ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astrophysique et traitement de l'image
Kidger, M.; Herschel Science Centre, ESAC, European Space Agency, 28691 Villanueva de la Cañada, Madrid, Spain
Lara, L.-M.; Instituto de Astrofísica de Andalucía (CSIC), Glorieta de la Astronomía s/n, 18008, Granada, Spain
Lellouch, Emmanuel; LESIA, Observatoire de Paris, CNRS, UPMC, Université Paris-Diderot, 5 place Jules Janssen, 92195, Meudon, France
Moreno, R.; LESIA, Observatoire de Paris, CNRS, UPMC, Université Paris-Diderot, 5 place Jules Janssen, 92195, Meudon, France
Rengel, M.; Max Planck Institute for Solar System Research, Max-Planck-Str. 2, 37191, Katlenburg-Lindau, Germany)