[BAA Comets] Introduction

[Tony Angel]

Hi,

Thank you for letting me join this group.  After reading through the past messages on here I can see that there are a few people I know. For those who do not know me I have been a member of the BAA for about twenty years, (though most of the time sitting at the back).  I have been spending a fair amount of time observing comets for the past twelve months. I am still low down on the comet learning curve.

I have mainly been doing basic imaging  - on average about five comets a night with exposure times between 5 and 30 seconds and between 20 and 240 per comet. Mainly I first image the popular ones and then go for dimmer mag 14 to 20 ones - though at the top end I get more negatives than positives, ( I have only managed one of C/2013 UQ4) . I have submitted a small number of images to the section.

I started to use Astrometrica with the help of Richard Miles (a lot of help!). I can get the astrometry to less than 1 arc second.  I have been reading George Alcock project pages so I know that I need to use two catalogues with Astrometrica to obtain the astrometry and photometry. I also realise that I need to learn FoCAs, Kphot, AIP4WIN,  Aladin and COBS to be able to produce results good enough for submission to the Comet Section as from what I can see the section is not interested in MPC formatted reports - is that correct? As I mentioned I am still low on the learning curve, so do not know how long it will take me to learn this tools, though I am slightly familiar with AIP4WIN and Aladin.

There are a couple of things I am not clear about. The main one is to do with the number of observations and the time gaps per comet per observing session. Chatting to Charles Bell in the USA, he tells me that he takes a set of timed exposures and make 3 stacks, one  stack per submitted observation, each observation being 9 or more exposures . This usually gives him 3 observations over  30 to 60 minutes per target, though if it was a new target then the time span would be longer.  Does this fit in with the Section requirements.  He did mention that what he does was the same or similar to what Peter Birtwhistle does (I do not know Peter, but have seen his web site).

Most of the time I use a 2x2 binned ST8 with a C14 at F11 which gives me roughly an arc sec per pixel. I sometimes also use an ST7 on a 4" F4 Refractor for wider fields.  I am just starting to test a 24" F4 Newtonian which I have just installed, though I expect to have some teething problems.  I have a reasonable horizon. My location is 36.876426, -3.249940 on Google maps.  I normally manage to squeeze in about 200 nights a year.

Again thanks for letting me join.

Tony Angel