Observer: Richard Wainscoat
Location: Mokuleia, Oahu, Hawaii
Date: April 1, 1997 06:00 UT
The photo above shows the ocean and comet during twilight. The planet Mercury is visible low, underneath a small cloud at left-center (it is hard to see against the bright sky).
Camera: Nikon N90s Lens: AF Nikkor 28mm f/1.4 (@f/1.4) Film: Fuji Provia 1600 Exposure: 15 seconds, tripod mounted
Here is the comet after it became much darker. The short bright line is a boat; the fainter horizontal line shows waves breaking on the reef near the beach. At the left center, the zodiacal light can be seen. This is caused by scattering of sunlight from tiny dust particles that are spread in a disk-like cloud around the Sun.
Camera: Nikon N90s Lens: AF Nikkor 28mm f/1.4 (@f/1.4) Film: Fuji Provia 1600 Exposure: 2 minutes, tripod mounted
Here is a close-up view of the comet. The diffuse dust tail and the narrower blue ion tail are both clearly visible. The ion tail is shaped by the solar wind and points almost directly away from the Sun. The dust tail has a more curved shape, caused by radiation pressure from the force of the light that the dust particles absorb. The dust particles follow trajectories that are a combination of their orbital inertia and the outward push from the sunlight.
Camera: Nikon N90s Lens: AF Nikkor 80-200mm f/2.8 (200mm@f/2.8) Film: Fuji Provia 1600 Exposure: 2 minutes, equatorial mount, sidereal guiding
Copyright 1997 Richard Wainscoat, All Rights Reserved. rjw@galileo.IFA.Hawaii.Edu. You may make a copy of these photos for personal or classroom use. Please contact Richard Wainscoat if you want to use any of these photos for other purposes.
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