A megacomet glows in the dark in this long exposure image captured by an astrophotographer on June 18, before its closest approach to Earth.
Comet C/2017 K2 (PANSTARRS), referred to as K2, will pass close to our planet on Wednesday July 13 at nearly twice as far from Earth as our planet is from the Sun. But the comet, which can measure up to 160 kilometers wide, is still spitting up enough dust to be visible in telescopes.
“Look for a six-inch coma,” advised John Chumack of galacticimages.com (opens in a new tab), who found the massive comet in the constellation of Ophiuchus from a dark location in Yellow Springs, Ohio. (A coma is the cloud of gas and dust that a comet throws up as the sun heats its surface and lifts particles and molecules into space.)
Related: The giant comet was active much farther from the sun than expected, scientists confirm
At the time Chumack photographed the comet, it was at the celestial equator in the constellation Ophiuchus. It was visible in both a six-inch reflector and an eight-inch Schmidt-Cassegrain telescope, he added.
But the beauty shot 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 K2 to be magnitude 9.7 when he filmed it, and EarthSky (opens in a new tab) estimates that the comet could become as bright as magnitude 7 by the end of 2022. In comparison, magnitude 6 is about the darkest stars available to the naked eye, although the comet is harder to see. see because 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 binoculars 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 the next comet sighting.
Editor’s note: If you take a photo of the comet and would like to share it with Space.com readers, send your photo(s), comments, and name and location to spacephotos@space.com.
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