The Night Sky in May

Abstract

THE duration of night (sunset to sunrise) on May 1 in the latitude of London is 9.3 hours, decreasing to 7.8 by June 1. The moon is full on May 3 at 15.3h, and new on May 19 at 4.4h. A total eclipse of the moon, invisible from Great Britain, occurs on May 3. On May 5, the bright star P Scorpii (mag. 2.9) is occulted by the moon, the disappearance as seen from Greenwich taking place at 3h 34.5m at position angle 164° from the north point. Lunar conjunctions with the planets occur as follows: on May 9d 10h with Mars; on May 14d 23h with Jupiter; on May 16d 21h with both Venus and Saturn; on May 17d 14h with Mercury. Venus, Jupiter and Saturn are morning stars. Mars rises about an hour after midnight at the beginning of the month and just before midnight at the end. Mercury is not visible either as a morning or evening star. On May 12 at about 3h 45m it is worth looking at Jupiter when satellites I, II and IV present a curious arrangement on the east side of the planet. A corrected ephemeris for Comet Pons Winnecke (1939 c) is given in I.A.U. Circular No. 758. On May 17, the ephemeris places the comet 6° greater in declination than the star β Boötis. No ephemeris is available here for the bright comet, Comet Hassel, discovered on April 18 in the constellation of Andromeda. Solar activity is sufficiently high to warrant a lookout to be kept for auroras. (All times are given in Universal Time; add lh to convert to Summer Time.)