Comet P/2017 W3 (Gibbs)
Abstract
Alex R. Gibbs reports his discovery of a comet on CCD images obtained in hazy-clear conditions and average seeing with the Catalina Sky Survey's 0.68-m Schmidt reflector on Nov. 27 (discovery observations tabulated below); four co-added 30-s exposures showed a 6" coma that was elongated in the direction of a 20" tail in p.a. 300 degrees (which was fanned out about 20 degrees in p.a.). Follow-up observations by Gibbs with the 1.0-m reflector at the Mount Lemmon Station of Steward Observatory on Nov. 28.5 UT show a 5" x 6" coma elongated toward p.a. 290 degrees, where a tail was barely visible for 8" in four co-added 60-s exposures. 2017 UT R.A. (2000) Decl. Mag. Observer Nov. 27.51903 11 33 36.25 -10 51 53.2 19.2 Gibbs 27.52399 11 33 36.51 -10 51 54.9 18.8 " 27.52895 11 33 36.80 -10 51 56.7 19.0 " 27.53390 11 33 36.99 -10 51 58.1 19.1 " After the object was posted on the Minor Planet Center's PCCP webpage, other CCD astrometrists also commented on the cometary appearance. H. Sato, Tokyo, Japan, writes that ten stacked 60-s exposures taken with an iTelescope 0.61-m f/6.5 astrograph (+ luminance filter) at the Sierra Remote Observatory near Auberry, CA, USA, on Nov. 29.56 UT show a strongly condensed coma 6" in diameter and no tail; the total w-band magnitude was 19.4 as measured within a circular aperture of radius 3".7. S. Foglia and L. Buzzi measured ten stacked images taken by a large group on Dec. 2.26 with a 0.4-m f/8 reflector at Tenerife, and they find an 8" coma with a wide 20" long tail in p.a. 300 deg. E. J. Christensen notes that images taken with the 1.0-m reflector at the Mt. Lemmon Station of Steward Observatory on Dec. 13.5 show a diffuse coma about 8" across that is extended toward the northwest; his follow-up observations on Dec. 14.5 show a coma about 5" across, also extended toward the northwest.
- Publication:
-
Central Bureau Electronic Telegrams
- Pub Date:
- December 2017
- Bibcode:
- 2017CBET.4462....1G