Comet IRAS-Araki-Alcock, 1983 H1

Russell Milton
Location of photo
123° 29.6' W, 41° 26.9' N, on Klamath River, California, Elevation 644 ft.
Date/Time of photo
May 11, 1983, 5:50 UT
Mamiya-Sekor 1000 DTL camera with Pentax 200 mm f/4.0 lens, piggyback on Celestron-5, Kodacolor 400 film, 55 minute exposure
Comet IRAS-Araki-Alcock at closest approach to Earth, with an indication of a short tail to the right. Guiding was on the comet's nucleus. Length of the star trails reflects the comet's movement during the 55 minute exposure - about 2°. The field of view is around 10.3° X 6.9°. The jagged star trails are caused by seeing, the difficulty in guiding on a diffuse nucleus and periodic error from the spur-tooth drive. The bright pair of stars to the left of the comet is Theta and 26 Ursae Majoris, magnitudes 3.2 and 4.5.