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February 19: Mercury at greatest eastern elongation
Rising around 7:30 P.M. local time and visible all night and into the early-morning hours, Coma Berenices is home to a lovely star cluster cataloged as Melotte 111 and Collinder 256. Also called simply the Coma Star Cluster, this open cluster of stars lies in the northwest corner of the constellation, near the 4th-magnitude star Gamma (γ) Comae Berenices. The Coma Star Cluster lies adjacent to this golden-hued star, although Gamma itself is not part of the cluster, which lies far beyond this single star.
Spanning a hefty 4° on the sky, you’ll want a wide field of view to take in the entire cluster at once. Try using binoculars or even your telescope’s finder scope. In total, the Coma Star Cluster holds about 40 young suns that are about 400 million years old.
You may notice that, strangely, the cluster doesn’t contain any faint stars (below about 10th magnitude). Astronomers suspect it once held smaller, fainter stars, but the cluster simply wasn’t massive enough to hold onto these smaller suns over time, and they have since dispersed across the sky.
Sunrise: 6:46 A.M.
Sunset: 5:42 P.M.
Moonrise: 8:10 A.M.
Moonset: 9:33 P.M.
Moon Phase: Waxing crescent (15%)
*Times for sunrise, sunset, moonrise, and moonset are given in local time from 40° N 90° W. The Moon’s illumination is given at 10 P.M. local time from the same location.
