ASTRONOMICAL NOTES FOR DECEMBER.

Wairarapa Age, Volume XXIX, Issue 8302, 4 December 1906, Page 7

ASTRONOMICAL NOTES FOR DECEMBER.

(Special to the Age.) The SUN is in the constellation Ophiuchus till the 19th when he enters Sagittarius. His southern declination increases till the 23rd, when it reaches 23deg. 26 mins. 58 sees, of arc, its altitude at noon of the same day being nearly 78*5 deg. This is the longest day, not the 22nd of December. Sun spots were fairly plentiful during the early part of November, and should be looked for again from the sth to 15th.' The MOON, in her riionthly circuit of the heavens, comes into the vicinity of the planets and some of the brightest stars, and serves as a convenient pointer to them. She will be near the minor planet Ceres on'the night of the Ist, Jupiter on the 4th, Neptune on the same date* Mars on the 12th, the minor planet Juno on the same date, Venus on the 17th, Saturn on the 21st, and Jupiter and Neptune on-the last of the month. She will pass through the following constellations on the following evenings, and in the order stated :—Capricornus on the evenings of the 18th and 19th, Aquarius on the 20th and 21st, Pisces on the 22nd to the 24th, Aries on the 25th and 26th, Taurus on the evenings of the 27th, 28th, and 29th, and Germini on the 30th and 31st. Her considerable southern declination while in the first quarter still offers great advantages for the successful study of her surface at this time. PHASES OF THE MOON, in New Zealand mean time: —Full moon, lday 10 hre 37 mins. a.m.; Last Quarter 9days lhr. 15 mins. p.m.; New moon 16days 6hrs 24 mins, a.m.; First Quarter 23days 2hrs. 34mins. am.; Full moon 31 days 6hrs. 14mins. a.m. The moon is seen to be "full'"twice during December. She is also twice in Apogee, viz., on the 2nd anfl 29th. MERCURY is a morning star at the beginning of the month rising about half an hour before the sun. His path is a retrograde one in Scorpio till the 10th, when he again moves forward. He will bo in perihelion on the Ist; at greatest heliocentric latitude north on the 12th; in conjunction with Venus on the 14th, and with the moon on the same date; and at greatest western elongation on the 19th. ' VENUS from being the resplencV ant star of the western sky has once more passed into the overpowering rays of the sun. She is now a morning star, rising at the beginning of the month nearly half an hour in advance of the sun. Her path is retrograde in Scorpio till the 20th, when she again moves forward amongst the stars. A most interesting phenomenon to possessors of astronomical telescopes takes place on the early morning of the 10th, when this planet passes before the star Beta Scorpii. Time will vary for different positions in New Zealand, but Dr. Downing, F.F.A.S., computes it for Wellington at 4hrs 47miris. a.m. for the star's immersion, and shrs 42mins for the emdersion. It is to be regretted that this phenomenon is beyond reach of the naked eye star-gazer, taking place as it does after sunrise. Venus will be in conjunction with the moon on the 14th. MARS is a morning star during the month, rising about two and a quarter hours before the sun on the Ist. His path is a forward one in the constellation Virgo, He will be in conjunction with the moon on the 12th. JUPITER is now the evening star, taking the place of Venus in the west by presenting his brilliant disc in the Eastern sky shortly after 9 p.m. ab the beginning of the month. He will repay observing later in the evening, when at sufficient elevation from the • horizon. He is in conjunction with the moon on the early morning of the 4th, in opposition on the 29th when v he is at his most favourable position for the telescopic observer, and in conjunction with the moon again on the last of the month, 2-3 deg. to the north. SATURN is still in a favourable position for the observer, moving fbrward in the constellation Aquarius. He is in quadrature (with the sun) on the 2nd, and in conjunction with the moon on the 21st, to the north 1-2 deg. Those who wish to see the ring system of this planet before the edge is quite turned towards us, and it becomes invisible, should not miss the present opportunity. ' URANUS is an' evening star in Sagittarius, moving forward amongst the, stars of that constellation. He ■will be in conjunction with the moon on the 17th, and will pass into the same right ascension as the sun .on the last day of the month. NEPTUNE is an evening star in the constellation Gemini, having a retrograde movement. He will be in conjunction with the moon on the morning of the 4th and again on the 31st, METEORS.—No well marked meteors were seen at this station from the radiants in Leo or Andromeda, but several very fine ones were reported from other positions. Gemini and Taurus have given interesting displays during the early part of the month. They are generally noted to be amongst the most swiftly moving visitants of this.class, and should be looked for from about the 4th to the 14th. The CONSTELLATIONS at the middle of the month for 'about JB.p.m..are as follows .-—Aries,,Cetus, and part of Taurus, containing the Pleiades and Hyades to the north; Pisces and Andromeda in the northwest and the remainder of Taurus .with Orion Major to the north-east. brilliant Sirius, withflQrion, and the fine zone of stars and Milky Way towards Argo, are the chief objects offering attraction in ijhe east, while to >the south the Cross is seen rising, from beneath the Southern Pole, followed

by the bright pointers, Alpha and Beta Centauri. Canopus lies between Sirius and the Cross. To the west may be seen the last of Sagit tarius, with Capricorn and Aquarius following downward to their setting. Looking towards the north, at the beginning of the month, at about 9 p.m., and at nearly a third of the distance from the horizon to the zenith, there will be noticed the triangle formed by the three principal stars in Aries. At about another third of altitude is a similar but larger triangle a little to the east. If a line is carried along the two upper stars of this higher triangle, which is a part of Cetus, and this is produced about the same distance to the left, it will carry one to the position of the noted star Mira Ceti, or the "Wonder Star" the Whale. This is one of the best known of the variable stars, and its career has been watched for upwards of 300 years. From being invisible for several- months, to the naked eye, it mounts up to the brilliancy of a second magnitude star, then after a few weeks begins to decline again, and is soon lost to view by the unassisted vision. This variation of brilliancy is accompanied by considerable differences in the periodcity as well as colour changes, making it one of the problems in astro-physics. This star will be at maximum brilliancy about the 19th. THE HON, DIRECTOR, Wanganui Observatory. November 30th, 1906.