Comet C/1999 S4 LINEAR was discovered
with the Lincoln Near Earth Asteroid Research (LINEAR)
telescope operating in New Mexico, USA. It passed perihelion (closest approach to the Sun) on July 26, 2000 at a distance
of 0.76 AU (about 115 million km). The comet was closest to Earth almost at the same time (July 23) at a distance of 0.37 AU (about 56 million km).
Comet C/1999 S4 became a binocular object in late June and brightened to about 6th magnitude until late July, though it never reached naked eye
visibility. Images and CCD V-filter photometry, obtained at Crni Vrh Observatory show daily
changes in comet activity. According to July 23-27 observations
by M. Kidger (Instituto de Astrofisica de Canarias), the comet nucleus disrupted
completely after July 23, resulting in further fade of comet brightness. Similar disruption
(or possibly turn-off in nucleus activity) was observed at comet C/1996 Q1 (Tabur) in late October 1996.
Since we followed the comet motion on most of our images, the stars appears as rows of dots or short trails. False-colors have been added in
order to bring out the comet details as much as possible. In order to cover the comet apparition as good as possible, some high quality images
from Italian observers Rolando Ligustri and
Giannantonio Milani have been added.
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