For you non-astronomical types: I-filter is 0.9 microns (800 nm)
J-filter is 1.25 microns (1250 nm) Visible is about 0.6 microns Larry On Mon, October 29, 2007 5:29 pm, Ron Baalke wrote: > > POSSIBLE DETECTION OF A SHORT TAIL BEHIND COMET 17/P HOLMES > Universite de Montreal > October 29, 2007 > > > Montreal - The recent brightening of comet Holmes has > spurred a frenzy of observations both by amateurs and professionals > astronomers alike. All these observations reveal a tailless round > yellowish fuzzball in the constellation Perseus. Near infrared images of > comet P/17 Holmes, obtained with the 1.6m Ritchey-Chretien telescope at > Mont Megantic Observatory (Qc, Canada), indicate a small tail-like > feature next to the comet's head. > > The images were obtained by graduate student Sandie Bouchard and > night assistant Bernard Malenfant on the morning of October 26, using > SIMON, a Near Infrared Polarimetric Imager. > > > A preliminary analysis, performed by astronomers Pierre Bastien and > Rene Doyon from Universite de Montréal and the Centre de Recherche en > Astrophysique du Quebec (CRAQ) clearly shows a bright elongated feature > surrounding the more luminous comet's coma. This elongated feature, > probably a cloud of dust and gas, which resembles a small tail, is going > out at position angle of 145 degrees (+/- 5 deg), measured from north and > going east. This direction makes an angle of about 33 degrees relative to > the Sun-comet direction. Although the images display tantalizing evidence > of a tail, the direction of the feature does not point directly in the > direction opposite to the Sun, as expected. > > For more information, contact: > Dr. Pierre Bastien > Universite de Montreal > Tel: 1-514-343-5816 > Email: [EMAIL PROTECTED] > > > Image caption: The following raw images were taken with the NIR > instrument SIMON. On both images East is up and North is right. > > Fig.1 : image taken with an I filter Oct 26 at 04:37 EDT (08:37 UT) > Fig.2 : same as fig.1 but with a J filter taken at 04:10 EDT (08:10 UT). > > > http://www.astro.umontreal.ca/~casca/PR/holmes_I.png > http://www.astro.umontreal.ca/~casca/PR/holmes_J.png > > > PIO Source: > Robert Lamontagne > Attache de presse/Press Officer > Societe canadienne d'astronomie/Canadian Astronomical Society (CASCA) > Dept. de Physique Tel: 1-514-343-6111 > (p.3195) > Universite de Montréal Telecopieur: > 1-514-343-2071 > C.P. 6128, Succ. Centre-ville > Montreal, Que. H3C 3J7 Courriel: > [EMAIL PROTECTED] > > ______________________________________________ > Meteorite-list mailing list > Meteorite-list@meteoritecentral.com > http://six.pairlist.net/mailman/listinfo/meteorite-list > > ______________________________________________ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list