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March 21: It’s Messier marathon night
Asteroid 7 Iris is drifting through Sextans, passing close to a close pair of stars that provides an anchor for those looking to watch the space rock’s movement across the sky. Step outside early this evening and look southeast to find the constellation Sextans, located just to the lower right of the lounging figure of Leo the Lion as it rises in the sky. Today, Iris is 2.6° north of mid-4th-magnitude Alpha (α) Sextantis, and about ¼° southwest of an uneven doublet of stars (these require optical aid to spot). Sitting in roughly an east-west line, the brighter of these suns is 7th magnitude, while the fainter is 8th magnitude. Iris, now magnitude 9.4, is fainter than either of these, but closer to them than any background stars. Use this pairing as an anchor point and you may be able to see Iris’ slow drift across the sky over the course of three or so hours.
Sunrise: 7:00 A.M.
Sunset: 7:14 P.M.
Moonrise: 8:40 A.M.
Moonset: —
Moon Phase: Waxing crescent (21%)
*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.
