ASTRONOMICAL NOTES FOR JANUARY 1915.

Pukekohe & Waiuku Times, Volume 3, Issue 260, 29 December 1914, Page 3

ASTRONOMICAL NOTES FOR JANUARY 1915.

(Contributed by Mr L. J. Comrie), It is my purpose in this series of monthly notes to present a forecast of astronomical phenomena in such a way as to interest those who aie not fortunate enough to have any technical knowledge of the subject. To this end I sball endeavour, month by month, to give an accouut of all features of special interest in connection with the sun, moon and plaretN, together with a description of the principal fixed stars visible for the time being.

THE SUM. The sun's path this month will be through the constellations Sagittarius and Capricornus, which will consequently be invisible to us. On the 2nd the earth is in perihelion, i.e., it is closer to the sun than it is at any other time during the year, it must not be imagined that any warm weather experienced at this time is due to this nearness, for, at a matter of fact, the sun's variation from its mean distanca from us (93,000,000 miles) only amounts to one and a-half million miles, and that is insufficient to affect our climate appreciably.

THE MOON. The phases of the moon will be as follows: —

Full moon, January Ist, 11.50 p.m. Laßt quarter, January 9th, 8.43 a.m. New moon, January 16tb, 2.12 a.m. First quarter, January 23rd, 5.2 p.m. Full mooo, January 31st, 4.11 p.m. Perigee, January 13tb, 1.30 a.m. Apogee, January 24tb, 8.0 p.m.

The terms Perigee and Apogee will perhaps require explanation. The moon is said to be in Perigee when she is at her nearest to our earth, and in Apogee when she is at her farthest. Her mean distance is 239,000 miles, and she can vary 13,000 miles un either eide of this. It will be noticed that there are two full moons tbis month; next month there will be none while in Match' there will again be two. There are thirteen full moons each year so that in general some month has two in each year; but in tbis particular year January has stolen February's moon, and March has got the extra one. Such an occurrence is not likely to happen again in any of our lifetimes.

PATH OF THE MOON. On the Ist the moftn is full in Gemini—the Twins—forming in the early part of the evening a triangle witn Saturn and Betelgeuie (see later). On the following evening it will pass close to the Twins Castor and Pollux. When it rises on the sth the bright star Regulus, of the Lion, will be seen juat off the dark limb, i.e., on the westward side. On the 18th, after sunset, the muon in Aquarius will be a few degrees to the eastward of Jupiter. There will be no occulations of Jupiter, or indeed of any of the bright planets visible in New Zealand this year. During the evening of the 23rd our satellite will form a small triangle with the two principal stars in Ariea-the Ram. Two nights' later she passes through the well- known group the Pleiades; with a fairly powerful opera glass this should be an interesting spectacle. On the 26th, at 7.30 p.m.. the moon will be approximately on the meridian, and ten degrees north of the ruddy star Aldebaran. On the following night at the same hour, and later, one will see the second magnitude star Beta Tauri on the westward limb uf the mooo; here again the opera glasses may be useful. On the 28th this same s tar and Saturn will form a triangle with the moon. For the next two eights it will again be in Gemini close to Castor aod Pollux.

MEKwUKY, Being in superior conjunction with the sun on the 6th will not be visible until the last week of the month, when it will be seen as an evening star in Gapricornus a little below Jupiter. VENUS.

This planet was the wonderful "Day Star" that attracted so much Attention at the end of October last.

She will be visible to the naked eye in tbe daytime all thin month if one can but look in the right place. Since she will also be a morning etar the best plan would be to detect her before tunrise and lollow her all day. She attainß her maximum brilliancy on the 2nd and 3rd. On the 12th and 13th she will be about ten degrees to the north of the muon, which will be on the meiidian, roughly speaking, at 9 a.m.

MARS I j now too close to the sun for observation, but will be a morning star later in the year. JUPITER.

For the first belf of this month Jupiter is in Capricoinus, and afterwards in Aquarius. He id an evening star at present, tut in the beginning of February will disappear, to reappear several months later as a morning stir. He is the largest of all the planets, largest in fact than all the others put togethir, and vet is less than tbe onethousandth part of the sun. He has eight satellites, four of which are visible in an opera glass, but the season for favourable observation has now passed.

SATURN. Having just passed his opposition, is well situated for observers. It is persuing a retrograde path in Taurus between the third magnitude stars Eta Geminorum and Zeta Tauri. The latter star, together with Beta of the same constellation represented in the eyes of the ancients the horns of the Bull. Saturn is, as everybody knows, the planet with the wonderful rings, but these are viable only in telescopes, although a small instrument will suffice to show them. In my estimation these rings take a high position in the six most beautiful objects to be seen through a telescope. One should not fail to notice when looking at Saturn that his light is much steadier than that of the fixed stars, and that he does not twinkle. This is characteristic of all the planets. THE FIXED STARS.

Sir Robert Ball, a famous astronomer who died just recently, says in his excellent work "The Story of the Heavens," that "every student uf astronomy should make himself acquainted with the principal constellations of the heavens." Now, I wibh to introduce to you one of the brightest constellations visible this month. 1 will start by assuming that everybody can recognise Orion's Belt, sometimes called, the Pot or the Chair. It conbißta of three second magnitude stars symmetrically placed in a straight line., the distance between the two extreme stars being two and a-half degrees, or about four times the width of the moon. By producing this line southward for twenty degrees one is led to Sirius or the Dog Star, the brightest of all fixed stars. So bright indeedjs Sirius, that he gi\es as much light as a thousand of the faintest stars that we can see with the caked eye. He is the principal star ot Canis Major or the Greater Dog, which was reputed to be one of Orion's Hounds. The ancients reckoned the "dies caniculaies", or dog days, from the heliacal rising, i.e., rising with the sun, of Sirius. Among the precepts left by Thean Alexandrines, an ancient astronomer, was one "to find the exact time of the dog star's rising with the sun; twenty days before which, and twenty dayß after, including the period of extreme heat, hydrophobia and other evils." Ten degrees perpendicularly above and below the belt of Orion will be seen two brilliant stars; the upper of these Is Rigel, and the lower one, which is somewhat ruddy, receives the name of Betelgeuse. This latter star and the middle star of the belt fotm the base of an approximate equilateral triangle, the northern apex of which is occupied by a second magnitude star, Bellatrix. Similarly Kigel and this middle star form a triangle with Kappa Orion is on the south. These four stars—Betelgeuse, Bellatrix, Kigel and Kappa Orionis-form a quadrilateral, the belt being in the centre. Above i,the right hand member of the belt is the famouß Sword of Orion. It consists of three stars in a short line pointing to the middle of the belt. On a clear night a keen eye can resolve the upper and brightest of these three stars into two. Around the middle star, Theia Orion is, is situated the Great Neuula in Orion. Viewed through an opera glasß, one sees a hazy mist surrounding a double star.

Orion, next to the Southern Cross, is the best known constellation in the Southern Hemisphere. It is mentioned in the Bible in Job and Amos; the Mosaicists, however, called it Nimrod, who like Orion waß a mighty hunter. A line northwards from Bellatrix, parallel to the Belt, leads to Aldebaran fifteen degrees away in the eye of the Ball, and if continued an equal distance to the well-known Pleiades. This latter group, situa'ed in the shoulder of the Bull, is perhaps the most popular group in the whole sky. It is sometimes spoken of as the Hen and Chickens, or the Seven Sisters, while Amos exhorts Israel to "seek Him which maketb the seven stars and Orion," although Job refers to them by their usual name. Although they have been named the "seven stars" yet to most eyes six only are usually visible. On brilliant moonless nights the eeventh can be seen, and sometimes more. I have on one occasion counted eleven; with a email binocular, however, thirty or forty may be counted. A second magnitude star, Beta Lauri, forms a rightangled triangle with Bellatrix and Aldebaran, the latter being at the right angle. A line fram Bellatrix through this star 'leads on to Capella, m Auglra the Chaviotcer. Or we may profitably take the Rhymer's advice, Nath being Beta Lauri

From Rigel lise, and lead a line through Beatrix's Pass Natb, upon the Bull's north horn, and gain Capella's height.

Capella vies with two other stars for the honour of being the fourth' brightest in the sky, but unfortunately never rises very high in these latitudes. Saturn is in this region approaching Zeta Lauri, a star on the line from Betelgeuse to Beta Lauri. It is brighter than the former star, and if watched for several weeks ,v 1 li- i<ccn <o change its position. ,\ :ine trot Kigel between the middle find riu t hand members ot iiriun d t.eit, n ads, if produced two ::Mfi n half Unns its own length, t a ■»ecf'nd magnitude star, Gamma

ueminorum. From here a big sweep through Siriua leads on to Canopus, now high up in the sky. Not only is this star the principal one in tbe constellation of Argo Naira or tbe Ship Argo, but it is the second brightest fixed star. An almost perfect equilateral triangle is formed by Siriua, Betelgeuse and Procyon of Canis Minor or the Little dog. It is of this star that an astrologer once remarked in the quaint language of his day, "What meteoroscoper, yea, who learned in matters astronomical, noteth not the (tfects at the rising of the starre called tbe Litel Dofge." The Twin* Caster and Pollux are at the apex of a triangle, the baie of which is formed by GammafGeminorum and Procjon. Pollux is slightly the brighter of tbe two. Time and space prevent me, for this month at any rate, from giving the interesting legends connected with these and other stars. Lastly, I would like to point out that a line from Betelgeuse through the right of the bait leads into the constellation of Lepra or the Hare. Next month 1 hope to explain what is meant by the magnitude of the atars, and the system of naming stars.

All times given in these notes, and any that may follow, have been worked out for the latitude and longitude of Auckland, and reduced to New Zealand mean Civil time, ehven and a-half hours fast of Greenwich. The times may be taken as correct within a radius of fifty or sixty miles from Auckland. This appliea particularly to phenomsna in connection with the moon, except the phases, which are the same for all parts of New Zealand.