As the sun sets Friday, see if you can spot Mercury dangling low against the southwest horizon before it too sets within a half-hour. While fleeting, this is Mercury’s best evening apparition. At this point, Mercury is at its greatest eastern elongation, meaning that, as seen from Earth, the innermost planet is its farthest to the east of the sun, in this case 24 degrees. Even at its best, Mercury is a tough target, often easier to spot scanning the horizon with binoculars.
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