The Night Sky in June

Abstract

THE nights around the summer solstice on June 21 are shorter than 7J hours in the latitude of London, reckoned from sunset to sunrise; excluding twilight (nautical) darkness lasts only about three hours. The moon is new on June 6 and full on June 19. Venus, which is still a brilliant evening star at the beginning of the month, draws rapidly towards the sun's place and is at inferior conjunction on June 26. Mercury is also an evening star in conjunction with Venus on June 12 and with Mars on June 17; on June 24 Mercury is at greatest elongation (25° east). Mars is getting less easy to see; it is close to Venus on June 7. Jupiter and Saturn are both morning stars, the former rising soon after lh. 30m. U.T. on June 16, followed ihr. later by Saturn. At dusk in mid-June, the red star Antares is about south. Arcturus has already southed, while Vega is some 3 hours before the meridian. The constellations, Bootes, Hercules and Ophiuchus contain some interesting double stars of which e Bootis (2-8″), Bootis (·1″)> a Herculis (4-8″) and 70 Ophiuchi (6-6″) are good examples. Between A and B Herculis may be glimpsed with the naked eye under favourable conditions the great star cluster, ?13, the distance of which is of the order 35,000 light years. The outer part of the cluster can be resolved into stars with a 2-B- or 3-inch refractor. The Scorpiid meteors are at their greatest frequency about June 4, their radiant point being north, following Antares.