THE SUPER-SIZED NUCLEUS OF COMET NEOWISE: Now we know why Comet NEOWISE (C/2020 F3) is so bright. It has an unusually large nucleus. Infrared data from NASA's NEOWISE spacecraft suggest that the comet's core of ice and dust is 5 km wide. This bodes well for the comet's visibility in the weeks ahead. Visit Spaceweather.com for the full story and observing tips.
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Above: Naked-eye Comet NEOWISE over Bluff, Utah, on July 9, 2020. Credit: Paul Martini. For more photos, browse the Comet NEOWISE Photo Gallery.