NEW COMET NISHIMURA MAY BECOME NAKED-EYE BRIGHT

by astroport
July 29, 2023

Newly discovered Comet Nishimura is quickly brightening in the morning sky and may be faintly visible with the naked eye next month. On August 24th observers in North America will be treated to an occultation of Antares.

Newly discovered Comet Nishimura is quickly brightening in the morning sky and may be faintly visible with the naked eye next month. On August 24th observers in North America will be treated to an occultation of Antares.

Comet Nishimura C/2023 P1Comet Nishimura slides between NGC 2392 (top) and the galaxy UGC 3873 in Gemini on August 19, 2023. The coma glows blue-green from diatomic carbon emission while a spiky ion tail extends to the west.
Dan Bartlett
It’s no small thing for an amateur to wrest a comet from the all-seeing eyes of robotic surveys. But Japanese observer Hideo Nishimura beat those odds on August 12.8 UT. That morning he took three 30-second exposures with a Canon 6D digital camera and 200-mm lens and captured images of a new 11th-magnitude comet in the constellation Gemini. It was his third comet discovery after Comet Nakamura-Nishimura-Machholz (C/1994 N1) and an earlier Comet Nishimura (C/2021 O1). I have nothing against automated hunting, but seeing an amateur’s name on a comet is not only a breath of fresh air but a great achievement.

Comets are like presents under the Christmas tree waiting to be opened. On August 15th the sky cleared and I found a location with an unobstructed view to the east to get my first look. At 4 a.m. local time Comet Nishimura stood just 8° high in the northeastern sky in Gemini. Through my 15-inch (38-cm) Dob I saw it right away at 64× at magnitude 9.8 with a 2.3′ moderately condensed coma. A Swan band filter enhanced its visibility and intensified the apparent brightness of the inner coma, a sign that Nishimura’s comet was rich in volatile carbon gas.