199P/Shoemaker wakes up

Sometime in the last couple of days periodic comet 199P/ Shoemaker went into outburst. Gustavo Muller (MPC J47) was the first observer to report an amazing brightness increase as the comet went from being a 17.90 mag. object in mid-July to reaching 14.53 mag. (10" arc seconds box) on August 3, 2008. An image of the first report can be seen at his site: http://astrosurf.com/nazaret/images/cometas/199/199-080803-J47.jpg

With the very recent memory of 17P/Holmes in mind (also discovered from the Canary Islands by Juan Antonio Henríquez Santana, MPC J51), I decided to image comet 199P in spite of its terrible location in the sky as seen from my observatory (very near the Barcelona light dome).


A very bright core can be seen surrounded by a tenuous but evident envelope of material. The image is zoomed and no processing has been applied to the stacked image. The photometry is as follows and was calculated in the unfiltered images for different boxes with FOCAS software (by Julio Castellano) against the USNO A2.0 R catalogue.

                     10x10  20x20  30x30  40x40  50x50  60x60
FECHA      HORA          ±     ±      ±     ±      ±      ± 
---------- --------  -----  -----  -----  -----  -----  -----
04/08/2008 20:08:47  14.48  14.26  14.18  14.16  14.14  14.15
04/08/2008 20:08:47   0.04   0.07   0.13   0.12   0.08   0.09

On August 7, 2008 I took more images in spite of the presence of a very young Moon.


Photometry carried out this second night shows a slight decrease of brightness in the 10" aperture but an overall steadiness (if not a slight increase) at the 60" box.

                     10x10  20x20  30x30  40x40  50x50  60x60
FECHA      HORA          ±     ±      ±     ±      ±      ± 
---------- --------  -----  -----  -----  -----  -----  -----
07/08/2008 20:18:48  14.59  14.25  14.18  14.13  14.10  14.05
07/08/2008 20:18:48   0.06   0.11   0.12   0.11   0.15   0.16

Comet C2007 W1 Boatini at its best

What a difference some months make! Comet Boattini was less of an impressive sight back in march, but is now a very bright body displaying lots of detail, having now passed its closest aproach to the Sun at the end of June at some 0.8 AU.

A screen shot from "Orbitas" (a great free software package from Julio Castellano) illustrates how the brightness of the comet has been increasing as it crossed perihelion.

Last night I left my telescope capturing as many photons as I could, and co-added the images together. The resulting image is very lightly treated with only a log scaling applied. A funny comma shape has been revealed in the last couple of weeks in images aquired and processed by Giovanni Sostero and Gustavo Muller.


The "intruder" at the bottom-left side of the image is mag. 12.5 asteroid Pomona.