See a passing comet this Sunday

See a passing comet this Sunday
This 120 second image of the comet was taken Dec. 2 by an iTelescope 50 mm 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. Credit: NASA

On Sunday, Dec. 16, the comet known as 46P/Wirtanen will make one of the 10 closest comet flybys of Earth in 70 years, and you may even be able to see it without a telescope.

Although the approach will be a distant 7.1 million miles (11.4 million kilometers, or 30 lunar distances) from Earth, it's still a fairly rare opportunity. "This will be the closest comet Wirtanen has come to Earth for centuries and the closest it will come to Earth for centuries," said Paul Chodas, manager of the Center for Near-Earth Object Studies at NASA's Jet Propulsion Laboratory in Pasadena, California. What's more, Chodas said, "This could be one of the brightest comets in years, offering astronomers an important opportunity to study a comet up close with ground-based telescopes, both optical and radar."

Comet Wirtanen has already been visible in larger amateur telescopes, and while the brightness of comets is notoriously difficult to predict, there is the possibility that during its close approach comet Wirtanen could be visible with binoculars or to the naked eye.

Astronomer Carl Wirtanen discovered the comet in 1948 at Lick Observatory on Mt. Hamilton in Santa Clara County, California. With a width of 0.7 miles (1.1 kilometers), 46P/Wirtanen orbits the Sun fairly quickly for a comet - once every 5.4 years - making it a short-period comet. (Long-period comets, on the other hand, have orbital periods greater than 200 years.) At the time of closest approach, the comet will appear to be located in the constellation Taurus close to the Pleiades.

An observation campaign is underway to take advantage of the close approach for detailed scientific study of the properties of this "hyperactive" comet, which emits more water than expected, given its relatively small nucleus. The campaign, led by the University of Maryland, has worldwide participation across the professional and amateur astronomical communities. NASA-sponsored ground, air and space-based observatories getting in on the action include NASA's Goldstone Solar System Radar in California; the NASA Infrared Telescope Facility on Maunakea, Hawaii; the Hubble, Chandra, Swift and Spitzer space telescopes; and an airborne observatory known as the Stratospheric Observatory for Infrared Astronomy (SOFIA). The will even pass through the observing field of the Transiting Exoplanet Survey Satellite (TESS).

Explore further

We have a Christmas comet: How to spot interplanetary comet 46P/Wirtanen

More information: The Comet Wirtanen Observing Campaign website is:

Amateur imagery is available on multiple websites, including: , , … ible-to-eye-dec-2018

A NASA ScienceCast on Comet Wirtanen is available at: … u-light-up-our-night

Provided by NASA
Citation: See a passing comet this Sunday (2018, December 14) retrieved 19 July 2019 from
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

Feedback to editors

User comments

Dec 14, 2018
This was the original target of the Rosetta mission, before problems with the Ariane rocket caused delays.

Dec 15, 2018
Unfortunately, although the comet is likely to be 3.3 magnitude, it is the size of the full moon so the light is very spread out. The nucleus, very small will be visible. Binoculars as always, 50mm or larger objectives are advised.

Dec 15, 2018
I'll check it out with my 250mm reflector. Should be easy to see if it's near the Pleiades.

Dec 15, 2018
Sunday! Shoot, one might miss it. #Click-bait

With a five year period it must be going really-really-really fast, zipping out of view in no time.

Dec 16, 2018
Small smudge in 10X50 binoculars in a light polluted area. Skilled observers are seeing it under a dark sky with the naked eye.

Dec 16, 2018
Looking bad for tomorrow night. Clouded up this afternoon, no signs of relenting.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more