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Fri, 31 Jan 2003 - SPA Comet News, January 2003

Bright comets seem to be coming hot on the heels of each other at the moment. I was proven dramatically wrong that there were unlikely to be any more amateur visual discoveries, when Tetsuo Kudo and Shigehisa Fujikawa found a bright comet in mid December. It had in fact been visible in SWAN imagery, but the satellite team were running well behind with posting the images on the Internet and no-one spotted it until after the event. This was followed up with a CCD discovery by Charles Juels and Paulo Holvorcem on the first night that they tested a wide field imaging system.

Sebastian Hoenig's comet took an unexpected nosedive in brightness at the end of September. All the evidence points to the comet having been discovered a few days after it commenced a major outburst, which resulted in the disintegration of the entire comet. The other comet of the summer, 2002 O6, was named SWAN, rather contrary to the previous convention on naming such comets after the satellite that discovered them. It was quite a nice object, but low down in the twilight for most of the time. It too faded quite rapidly and it may also have disintegrated.

Comet NEAT (2002 V1) wasn't really expected to do very well, because when it was discovered it seemed to be quite a faint object that was unlikely to survive perihelion. It came into visual range in November and as the observations came in, it became clear that the comet was actually brightening quite rapidly. This rate of brightening has continued and the comet is now a binocular object and should be an easy naked eye object by the end of January. For February we will have to wait and see. Simple extrapolation of the light curve suggests a peak of perhaps -10, but this would be amazing to say the least. The comet could equally disintegrate, perhaps leaving behind a tail like the Cheshire cat's grin.

It is a conveniently placed evening object and it should be possible to observe it until mid February. If it really does become a brilliant object then it may be possible to follow it in daylight for another ten days. It will pass through the SOHO C3 coronagraph field between February 17 and 20. A bright comet offers many opportunities for amateurs. It should be very easy to photograph and may provide some splendid views for drawing and sketching. There may be interesting phenomena such as jets, hoods or fountains close to the nucleus, which often require high magnification to observe. Simple spectroscopes may show metallic emission lines. If there are few comparison stars visible, it is possible to reduce the apparent magnitude of the comet by observing through reversed binoculars with one eye.

Comet Kudo-Fujikawa (2002 X5) was discovered by Japanese amateur Tetsuo Kudo on December 13.83 with 20x120 binoculars and by his compatriot Shigehisa Fujikawa who independently found it in a 16cm reflector. Fujikawa is a well-known discoverer of comets and this is his 6th comet. Although reported as 9th magnitude at discovery, some observers quickly put it as bright as 7th magnitude. It isn't brightening very rapidly, but it had reached mag 5.5 and developed a short tail as it closed in on the Sun in mid January. It will soon be too close to the Sun for visual observation, but you may see it passing through the SOHO C3 coronagraph field of view between January 26 and 31. It then heads south (I am too and will be in Antarctica from mid February to the end of March), but if it maintains its present light curve we should be able to pick it up again in mid March. By then it will be a binocular object of around 8th magnitude and it will fade fairly quickly. There is some evidence that it too may have been discovered in outburst, as the light curve suggests that it could have been discovered a month earlier.

Comet Juels-Holvorcem (2002 Y1) is another object that wasn't originally expected to get within binocular range, but it too seems to be brightening quite rapidly. If it really is doing so, then it may become a binocular object in February, visible in the evening sky, and reach 5th magnitude in early April, though by then it will have become a morning object.

SPA members have been busy observing all these objects. Mike Feist has been making regular observations of 2002 X5 and has already glimpsed 2002 V1. Stephen Getliffe has been able to observe some of the fainter comets over the past few months and Cliff Meredith has been imaging both the bright comets. I had an amazing run at the beginning of January, making observations on every day for the first 12 days. This made up for December, which was a memorably cloudy month.

Springer have just published a new book on 'Observing Comets' and have generously made some copies available for competition prizes. The book is written by SPA Member Nick James and Gerald North and covers all aspects of comet observing. The SPA competition is to submit an illustration or drawing of a bright comet. This could be a fictional drawing, an imaginary view of an historic comet, a scenic photograph or a painting and can be on paper or sent as an image. Comet 2002 V1 (NEAT) may provide a real example to draw or photograph. The submission should be sent by post to myself at 11 City Road, Cambridge CB1 1DP or in electronic form by email. Please give your membership number when submitting. The winner will receive a copy of the book, and their submission, along with those of the runners up, will be published in Popular Astronomy. The closing date is April 16.

A meeting that should be of interest to all comet observers is a Pro-Am meeting on meteors, meteorites and comets that is being held at the Open University at Milton Keynes on May 10. There is an exciting range of speakers and the day will culminate in the presentation of the George Alcock Memorial Lecture by Brian Marsden. Competition prizes will be presented at the meeting to any winners that come along.

For more information on current comets, the latest updates on comets NEAT, Kudo-Fujikawa and Juels-Holvorcem and more details of the competition and meeting
see my web page. Updates on the progress of all the comets will be posted in the SPA ENBs.

Jonathan Shanklin

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