ASTRONOMICAL NOTES FOR MARCH, 1910

Otago Witness, Issue 2921, 9 March 1910, Page 89

ASTRONOMICAL NOTES FOR MARCH, 1910

(By John Geigg, F.E.A.S.).

THE SUN. The path of the sun during the month •will be from H.A. 22.40, Dee. S 8, in Aquarius, to R.A. 0.40, Dec. N in Pisces, or, in longitude, from 340.16 to 9.53, passing the Eqmnoctiail Co lure on the 21st at 11.3 pan., N.Z.T., at which time it is technically said to enter the “ Sign” Aries. Day and night are then equal all over the world. THE MOON.

Apogee , -<■<> -io p.m. THE PLANETS. Mercury will .be one and a-half hours in advance of the sun at the beginning of the month; subsequently gradually approaching and passing behind it. It will therefore become invisible to us. Venue will rise nearly two hours before the sun on the Ist, pass 12deg north of the moon on the 9th, and attain her greatest brilliancy as a morning star on the 19th. Mars is gradually receding from us, but may be found in the constellation of Taurus. The moon will pass near it on the 16th. Jupiter, which has reappeared to us, rising in the evening sky, will now be the planet of special interest, his brilliancy increasing as he approaches us Jupiter will be near the moon on the 26th, and culminate at midnight at the end of the month. Saturn, which for some months past has invited the attention of the possessors of telescopes on account of its convenient position for observation in the evening sky, is now getting low down in the northwest, its short path for the month being in the constellation of Pisces from R A 1.29 to 1.33, Dec. N 6to 7: the moon will be very near it on the 13th. Uranus rises about three hours before the sun, its position being R A 19.42 to 19.47, Dec. S, 21.48 to 21.37.

Neptune is still in Gemini, near the star Delta, its position for the month varying very little from R.A. 7.12, Dec. N. 21.44-. CULMINATIONS. The following bright stars, as seen from Dunedin, will culminate at the hours named, on the Ist of the month, and 3min 56sec earlier daily afterwards:

These times are calculated for the meridian of Port Chalmers, and reduced to New Zealand standard time llhr 30min fast of Greenwich. For inland places on or about the same latitude- one minute should be added for every 12 miles westward. If a compass is used for finding the meridian, allowance must ba made for its variation, which is given as 16.48 east of true north. HALLEY'S COMET. During the first half of the past month a few observations of this comet were mad© in New Zealand, and the positions noted agreed fairly well with those which had been computed for it. It wasi moving in a path a little to th© north of Saturn, the line of sight gradually approaching the sun. Its telescopio appearance was that of a very faint patch of light, and it could only be seen after sunset when the sky happened to be dark and clear. During this month the comet and the earth will continue their respective journeys on opposite sides of the sun, but as the latter will then bo in or near our line of sight, the comet will be invisible to us. In April, the comet gaining speed by its proximity to the sun, will pass rapidly round it and commence its outward iourney from its neighbourhood. Th© accompanying diagram of the orbits of th© earth and com©t shows their positions relatively to each other and to the sun for the year 1910. The email arrows indicate the lines of sight, earth to comet, and the dotted 'in© snows the position of the intersection of the pianos of the two orbits, which ar© at an angle of nearly 18 degrees, the comet being north of the ecliptic from January to May. July

The moon’s phases will be ae follows: — d. h m. Last quarter 4 n 22 p.m. New < O'- 11 11 40 p.tn. First quarter xi. 18. 3 7 p.m. Full ... iS r ■ 26 7 51 a.m. Apogree , .« 1 10 6 a.m. Perigee ... •• • A rv>froo ... 15 28 10 10 40 42 a.m n.m.

h. m. 3. Altitude. Canopus ... 7 50 12 S 83 10 Sirius ... ... ..; 8 15 33 . N 60 47 Castor ... ... 9 3 17 N 12 6 Pollux ... 9 14 2 N 15 56 Gamma Argus ... 9 46 55 S 88 45