How to See the Bright Green Comet 21P in Binoculars on Monday

Look up with binoculars early tomorrow morning (Sept. 10) to spot Comet 21P/Giacobini-Zinner whizzing across the sky. Here, astrophotographer Alexander Vasenin caught a photo of the comet from Moscow Oblast, Russia, on Aug. 18, 2018. Credit: Alexander Vasenin/Wikimedia Commons/CC BY-SA 4.0
Want to see a comet whizzing by Earth? A great chance to catch one of these celestial visitors is overnight tonight, when Comet 21P/Giacobini-Zinner will be best visible in binoculars or a telescope.

By Elizabeth Howell |

The comet, also known as „21P,“ will make its closest approach to Earth at around 2:30 a.m. EDT Monday (630 GMT). The bright-green comet should reach a visual magnitude of 6.5 to 7, according to This makes 21P almost bright enough to see with the naked eye — but not quite. [Bright Comets of 2018: When, Where and How to See Them]

To find Comet 21P in the night sky, look east and find the constellation Auriga sometime between midnight and dawn local time. The comet will still be visible even after tomorrow, but it will fade over the coming days. Its exact location from moment to moment is available in NASA’s ephemeris calculator.

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