A megacomet glows in the dark in this long exposure image taken by an astrophotographer on June 18 ahead of its closest approach to Earth.
Comet C/2017 K2 (PANSTARRS), dubbed K2, will swing by our planet on Wednesday (July 13) almost twice as far from Earth as our planet is from the Sun. But the comet, which can be as much as 100 miles across, still spews enough dust to show in telescopes’ fields of view.
“Look for a 6-inch coma,” advised John Chumack of galacticimages.com (opens in new tab), who found the massive comet in the constellation Ophiuchus from a dark location in Yellow Springs, Ohio. (A coma is the cloud of gas and dust that a comet ejects as the sun warms its surface, sending particles and molecules up into space.)
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When Chumack photographed the comet, it was on the celestial equator in the constellation of Ophiuchus. It is visible in both a 6-inch reflector and an 8-inch Schmidt-Cassegrain telescope, he added.
But the shot of beauty came from a slightly larger 12-inch F4 Newtonian reflector, Chumack added. Other equipment involved in the 31-minute exposure included a Bisque ME mount and a modified Canon 6D DSLR camera.
Chumack estimated that K2 had a magnitude of 9.7 when he captured it on camera and EarthSky (opens in new tab) Estimates suggest the comet could be as bright as 7 by the end of 2022. In comparison, the 6th magnitude is about the darkest star available to the naked eye, although the comet would be more difficult to see as it is diffuse.
If you’re looking for binoculars or a telescope to see the comet in the night sky, check out our guide to the best binocular deals and the best telescope deals now. If you need gear to capture the moment, check out our guides to the best cameras for astrophotography and the best lenses for astrophotography to make sure you’re ready for that next comet sighting.
Editor’s note: If you take a picture of the comet and would like to share it with Space.com readers, send your photos, comments, and your name and location to spacephotos@space.com.
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