Comet LINEAR C1999/S4

2000/7/22 The movement of the comet during this time period is already obvious. The comet tail is about half a degree in the photos. Both photos were 3 minute piggyback with 135mm/f2.8 Fuji800. The left one was take at 22:46 EDT, and the right one 13 minutes later. The map below shows the background stars. At that time the comet was brighter than the 6.6 magnitude star at lower left. From NEWO, Pittsburgh.

2000/7/22 23:53 EDT. Comet LINEAR as seen from the Wagman observatory. 50mm/f1.8, Fuji 800, 55 second exposure on a tripod. The yellow sky background was due to light pollution.

2000/7/22 Negative sketch of Comet LINEAR C/1999 S4. 8"/f6 Dob, 25mm eyepiece. The field of view is roughly 1degree. The left one was sketched at 22:50 EDT, the right one 23:25 EDT. The comet has moved quite a bit against the background stars. From NEWO, Pittsburgh.

2000/7/22 23:40 EDT Same as above except with a higher power (9mm) eyepiece.

2000/7/20 23:12 EDT 4 minute exposure with 135mm lens/f2.8, piggyback, Fuji800 film. From NEWO, Pittsburgh.

2000/7/8 3:45 EDT. Enlarged portions from a photo taken with 135mm lens, f2.8, 5 minutes piggyback, kodak 400 negative film. From NEWO, Pittsburgh.

2000/7/8 3:30 EDT. 50mm SLR, f1.8, Kodak 400 negative film, 5 minute piggyback photo on a Questar, hand tracking. From NEWO, Pittsburgh.

2000/7/8 1:25 EDT. It has developed a beautiful tail in larger telescopes. This is the negative sketch as seen in the 11" Brashear refractor at NEWO. However the comet is still a star-like spot in 7x50 binoculars with no sign of a tail.

2000/6/30 4:34 EDT. My first time observation of this comet. Fainter than I expected. Couldn't locate it with 7x50 bino, though the nearby M34 was obvious. Not too hard to find in a 8" Dob (thanks to M34). The left picture is a negative of my drawing (with 25mm eyepiece, FOV about 1 degree. North and West are marked in the picture. The texture of the comet is the artifact of image processing software), and the right one a more detailed sketch. The comet was dim, small, with the hint of a tail extending to lower right (or more like an elongated galaxy with one end slightly brighter than the other). The nucleus was not bright. Rough position: 2h 35m, 43.2N.

Twilight started as soon as I finished the drawings! Didn't get a chance to estimate the magnitude (the brightest star in the left drawing is about mag 7) or see it with a high power eyepiece. Will try again next time. Sky condition: clear, hazy, moderate city light pollution. Obs. location: backyard in Squirrel Hill, Pittsburgh.