Tuesday, September 15, 2009


IAUC no. 9072, issued on 2009, Sept. 11, announces the recovery of P/2003 A1 (LINEAR). This comet has been initially picked-up as a diffuse object (coma about 15-20 arcsec elongated in PA 280 deg) by R. A. Kowalski with the Catalina 0.68-m Schmidt telescope on 2009, Sept. 10.4.

Follow-up after its posting in the NEO-CP webpage was secured by several observers (P. Birtwhistle, G. Hug and the undersigneds), who noticed the presence of cometary features (in general, the existence of a small coma, about 10 arcsec in diameter with little or no central condensation, was reported).

D. Chestnov linked the new designated P/2009 R2 to P/2003 A1 (LINEAR). Probably due to a strong perturbation by Jupiter at the time of its aphelion (Sept. 2006), P/2009 R2 was found significantly off track (nearly 17 deg northeast of P/2003 A1 original ephemerids position).

IAUC No. 9073, published shortly after, informed us that B. G. Marsden successfully linked 14 astrometric data points collected in 1783 on comet Pigott (1783 W1) with the positions available so far on P/2009 R2 & P/2003 A1, establishing then that comet Pigott (1783 W1) had the same identity of P/2009 R2 & P/2003 A1.

Thus this object has been named as P/2009 R2 (PIGOTT-LINEAR-KOWALSKI).

M.P.E.C. 2009-R40, published on 2009, Sept. 11, details orbital solutions and preliminary ephemerids:

At first we imaged this object remotely, on Sept. 11.4, through the RAS network (MPC# H06, Mayhill, NM) with a 0.25-m, f/3.4 reflector + CCD: co-adding of 10 unfiltered exposures, 120-seconds each showed that this object was diffuse, without a clear central condensation (this created us some troubles establishing a useful photocenter for astrometrical purposes). Glare from a nearby field star prevented us to firmly establish a precise coma diameter, however in our images we saw at least 10 arcsec of coma.

Then we performed some additional follow-up on on 2009, Sept. 13.1, from the Malina River Observatory (MPC# B90, Povoletto, Italy) with a 0.25-m, f/11 reflector + CCD: stacking of 15 x 120-sec unfiltered exposures, confirmed the presence of a tiny coma, about 12-arcsec in diameter, with an extremely weak central condensation (40% illuminated Moon about 26-deg away).

Our image is available here:

by Ernesto Guido & Giovanni Sostero

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