IMAGING FOR SCIENCE 3$57 &20(76

Part 4: Comets

Your complete guide to capturing faint tails and calculating comet brightness and position data.

Amateur observations of comets can make a real contribution to science. But it’s recommended that you calibrate your PC or camera clock to an atomic time source before you begin any observations as astrometric and photometric measurements require timing precision. The date of observations should

Your photos can provide key information on the comets orbiting around our Solar System. Pete Lawrence explains how…

be noted, with time given in UT accurate to 0.00001 day (0.864 seconds). It’s also important to note the equipment used, including any filters, and the sky conditions.

If you plan to submit images or astrometry (measurements of position and movement) and photometry (measurements of brightness) to organisations such as the British Astronomical Association (BAA) you’ll need to use its standard format. For an image, indicate its orientation along with a scale; the convention for comet images sent to the BAA is to show north at the top and east to the left.

Astrometric measurements will need to have the precise location that the measurement was taken, including latitude, longitude and altitude. Observatories registered with the Minor Planet Center will have a code against which this information is held in a central database. Hardware & Software HARDWARE Binoculars, small and large telescopes, DSLR and CCD cameras

ABOUT THE WRITER Pete Lawrence is an expert astronomer and astrophotographer who holds a particular interest in digital imaging