Comet 46P/ Wirtanen, also known as the “Christmas Comet”, will be making a close pass of Earth on December 16, 2018, which will start appearing bright in the night sky this weekend. With its expected path, it’ll be at its closest distance to Earth in over 400 years. The comet will pass just 7,199,427 miles from Earth, making this one of the 10 closest comet approaches since 1950 and the 20th closest approach of a comet dating as far back as the ninth century.
U.S. astronomer Carl Wirtanen first spied the comet on the night of January 17, 1948, while surveying the sky from the Lick Observatory in California. Because he discovered it, the comet bears his name.
Comet 46P / Wirtanen is a member of the Jupiter family of comets, which means their farthest point from the sun is near the orbit of Jupiter. It will be bright enough to see with the naked eye above the eastern horizon all month long, and can be seen even better with a telescope and/or binoculars.
The image shared above from NASA is a 120 second image of the comet was taken Dec. 2 by an iTelescope 50mm refractor located at an observatory near Mayhill, New Mexico. The streak below the comet was produced by a rocket body (upper stage) passing through the telescope’s field of view during the exposure. Specifically, the upper stage is the one that placed the Indonesian Garuda 1 communications satellite into geostationary orbit back in February of 2000. At the time of this image, the Garuda 1 upper stage was 15,880 miles from the observatory; Comet Wirtanen was 10.3 million miles distant.
The comet will appear as a gray-green fuzzy blob in the night sky; some with a telescope may be able to detect a faint tail. Sky watchers should look toward the constellation Taurus, just west of Orion, which can be quickly found through the three stars of Orion’s belt. Comet Wirtanen will lie between two bright star clusters, the Pleiades and the Hyades.
Those watching the comet will get a double feature; the Geminid meteor showers will also be at their peak this weekend. NASA is forecasting as many as 100 meteors per hour, which should light up the night sky with frequent shooting stars.