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Comet 8P/Tuttle, 15 November - 12 December 2007

Inspired by Martin Mobberley’s article in the December 2007 edition of Astronomy Now, I tried to image Comet 8P/Tuttle near Polaris. My first attempt, a two-minute, unguided exposure on 15 November, was far from spectacular: it captured stars fainter than magnitude 15 and revealed the comet as the faint fuzzy patch in the centre of the frame. I persevered, taking images over the next few days but without achieving better results.

By early December, the comet appeared to be speeding up. Its movement can be deduced from a 20 minute exposure guided on the comet, taken on 05 December. See below - note the elongated star trails.

Despite windy conditions I was able to image Tuttle again just two days later. On 07 December, it passed the small, faint planetary nebula IC1454 (catalogued at magnitude 14.8 and just 33 arcsec in diameter). The image below shows the two bodies together; the small disc of the planetary nebula is clear to see. I combined 29 one-minute exposures to obtain the image and, during this period, Tuttle trailed significantly.

On 11 December, Tuttle was brighter and easy to find, passing just 1° from γ Cephei and heading rapidly south towards Cassiopeia. A day later it, it continued to brighten and I saw it for the first time in my 100 mm finder scope before I took the image below; it was due south of γ Cephei so very easy to find.

All images below were taken with a 16 cm F/2.5 Schmidt Camera and Starlight Xpress MX916 CCD. The full FoV is 75x56 arcmin (some thumbnails below are cropped). North is up.

20:38 UT on 15 Nov 2007 20:38 UT on 15 Nov 2007.

22:09 UT on 16 Nov 2007 22:09 UT on 16 Nov 2007.

20:24 UT on 29 Nov 2007 20:24 UT on 29 Nov 2007.

21:01 UT on 05 Dec 2007 21:01 UT on 05 Dec 2007.

20:20 UT on 07 Dec 2007 20:20 UT on 07 Dec 2007.

20:50 UT on 07 Dec 2007 20:50 UT on 07 Dec 2007. As previous image but guided on comet.

20:43 UT on 12 Dec 2007 20:43 UT on 12 Dec 2007.

20:19 UT on 11 Dec 2007 20:19 UT on 11 Dec 2007.

20:45 UT on 11 Dec 2007 20:45 UT on 11 Dec 2007. As previous image but guided on comet.


Mike Harlow