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Nothing to get too excited about. For a start, this same comet, 45P (where the ‘P’ indicates that it is ‘periodic’), flew by, even closer in 2011.
7.72 million mile separation is pretty respectable — 32x GREATER than the distance to the Moon.
So, don’t panic. Plus, it is quite a small comet, maybe a MILE across, max.
You may hear in the media that this the 8th closest approach by a comet. That is 8th closest as of 1950s when we really got good at measuring these distances — and you have to ALWAYS add, ‘KNOWN’.
This comet, 45P, even at this distance is unlikely to be naked eye visible!
So think of all the comet flybys our ancestors would have been oblivious to.