Why is Comet K2 so hard to see given its huge size? - Space.com

Distance is a factor.

As a huge comet makes its closest approach to Earth on Wednesday (July 13), you might be curious why it's so hard to spot. Comet C/2017 K2 (PANSTARRS), called K2 for short, is one of the farthest ac… [+4011 chars]

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