球状星团M3前方的李奥纳德彗星
2021年12月12日 Comet Leonard Before Star Cluster M3 Image Credit & Copyright: Dan Bartlett Explanation: Comet Leonard is now visible to the unaided eye — but just barely. Passing nearest to the Earth today, the comet is best seen this week soon after sunset, toward the west, low on the horizon. Currently best visible in the north, by late December th...