The Night Sky in September

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NEW moon occurs on Sept. 3d. llh. 21m., U.T., and full moon on Sept. 18d. 09h. 43m. The following conjunctions with the moon take place : Sept. 4d. 18h., Mercury 3° S.; Sept. 6d. 22h., Mars 0·7° S.; Sept. lOd. 13h., Jupiter 4° N.; Sept. 29d. 13h., Venus 6° S.; Sept. 30d. 05h., Saturn 4° S. In addition to these conjunctions with the moon, the following conjunctions take place : Sept. 9d. 10h., Saturn in conjunction with Regulus, Saturn 0·8° N.; Sept. 20d. 16h., Mercury in conjunction with Spica, Mercury 0-2° S. Mercury sets at 19h. 15m., 18h. 45m. and 17h. 52m. at the beginning, middle and end of the month, respectively, and is too close to the sun for favourable observation. The planet reaches its greatest eastern elongation on Sept. 25. Venus is a morning star, rising at lh. 15m., lh. 30m. and lh. 55m. at the beginning, middle and end of the month, respectively ; it has a stellar magnitude of approximately – 3·8 throughout most of September, and can be observed with phase a little more than half moon most of the time. The planet attains its greatest western elongation on Sept. 3. Mars sets at 20h. 10m. and 18h. 50m. at the beginning and end of the month, respectively, and is too close to the sun for favourable observation. Jupiter can be seen for some time after sunset, the times of setting being 22h. 25m. and 20h. 40m. on Sept. 1 and 30, respectively, but the planet lies rather low for good observation in northern latitudes. Saturn rises at 4h. 10m. and 2h. 35m. at the beginning and end of the month, respectively, and can be seen as a morning star, stellar magnitude 0·9. One occupation of stars brighter than magnitude 6 occurs as follows : Sept. 27d. Olh. 43·5m., 47 Gemi. (R), where R refers to reappearance ; the latitude of Greenwich is assumed. Autumnal equinox commences on Sept. 23d. 03h.