THE NIGHT SKY.

Taranaki Daily News, 27 September 1924, Page 9

THE NIGHT SKY.

NOTES FOR OCTOBER. (By “Sagittarius.”) The constellations which have gleamed from overhead during the winter months now begin to draw near to their setting in the west. Virgo, with its present visitor, the planet Saturn, seta with the sun about the middle of the month; Libra disappears soon afterwards, and Scorpio, our leading winter constellation, presently containing the giant Jupiter, sinks into the south-west and, quite early each evening, passes from our view. Sagittarius, too, is westering, but Capricornus still rides high and with it the red planet Mars. Aquarius makes its meridian passage about 8 p.m., while further over to the north of east the twelfth zodiacal constellation Pisces, the fishes, can be seen. About north, and lying between the two long starry tails of the fishes, a group forming a great square will be seen. Three of the four corner Stars belong to the constellation Pegasus, the winged horse, while the fourth, situated at the lower left-hand corner of the square, ia the star Alpherat, the leading star in t-he constellation Andromeda. AN OUTSIDE UNIVERSE. Just below Alpherat, possessors of keen eyesight can detect, on moonless nights, a faint misty-looking object. Thia is the great nebula in Andromeda, one of the most surprising objects which modern instrumental aid has made known to us. Seen in a powerful telescope, this nebula is revealed as an ellip'tieally shaped cloud of glowing splendour. Photographs show that it is a vast- spiral of stars and nebulae, apparently undergoing a wide rotary movement something like that of a whirlpool. Its distance and real size, however, are so vast that we cannot hope, with the means at our disposal, to detect any actual movement in this singular creation. The spectroscope informs ua that'it contains light-giving suns not greatly dis-similar from others which are nearer to us. and that it also possesses masses of nebulous material like those seen within the Milky Way;

At times, new stars have been observed to appear within its bounds, just as they occasionally do in our own galaxy, and it appears quite evident that we behold in this object a universe situated quite outside and apart from the atelia universe of which our solar system forms a comparatively tiny unit. In view of such a wonder as the Andromeda nebula presents, the human mind stands appalled, and speculation itself is brought to silence. A reverential awe falls upon the spirit, and that is surely well, for. in contemplating the unending possibilities connected with such stupendous systems as these, we seem to stand as in the immediate presence of the adorable Creator. A FAMOUS VARIABLE STAR. Among the many subjects of astronomical research is th&t of variable stars. It has long been known that some stars shine with a light which varies in brilliance from time to time. One of the first of these to be noticed was a star in the constellation Cetus, which lies above Pisces and the great square in Pegasus. The star in question is named Mira, or the “wonder” star. It should be looked for about 5 degrees above the brightest star in Pisces. It will be looked for in vain, however during October this year, as at present (Mira is only about an eighth magniture atar and can only be seen in a good telescope. At minimum brightness this remarkable member of the heavenly bodies is only of magnitude 9.7; it is getting brighter at present, and, at its maximum brilliance, which it reaches in December, it will attain to nearly magnitude 2. Its entire period between two maxima is 32J days. Until quite recently we could only imagine the possible cause of such strange behaviour on the part of this distant sun, but it is now known that Mira consists of a pair of suns so related in position to each other that as they revolve about their common centre of gravity they present the phenomena of mutual eclipses; phe light appearing to us to fade when the two stars are in line and increasing as they separate from each other. THE PLANETS. Saturn, low down in the west, will be in conjunction with the moon on the first of the month. Jupiter will be in conjunction with our satellite on the 4th; Mars on the 9th; Uranus on the 10th; Neptune on the 23rd; and Mercury on the 2Sth. Venus is still a morning star and can be seen in the east before sunri»e. Mars is rapidly receding from us, but is still a conspicuous object. It reaches the meridian at 8.25 p.m. on the 15th of the month. The complete reports of observations of Mars during the recent opposition will dot come to hand for some time. COMETS. A new comet is reported, and is to be searched for in the constellation Bootes, some degrees south of the bright etar Arcturus. At the time of writing the weather conditions, locally, prohibit any attempt to pick up the stranger; but it is probable that before long some observation of our visitor will be made. It is now 14 years since a spectacular comet approached the earth, so it may be hoped that the one recently discovered will increase in 'brightness sufficient to afford a good view of a member of the comet family, than which no stranger objects come within our ken. Our knowledge of these fiery visitants to our system is still far from complete. Nor is it yet possible to definitely assign a reasonable cause for their presence in the universe. The tremendous impression which their appearance has made upon the minds of ignorant men is now largely diminisneu owing to the widespread reports of what astronomers have discovered of the nature of these bodies, yet even so recently as 1910, when Halley’s comet made its sensational appearance, primitive races were greatly disturbed at beholding the strange aspect of the celestial visitor.

It would seem, however, that the risk of the earth colliding with, a comet is exceedingly small; probably two toy balloons, one sent up at Invercargill and one at Auckland, would stand a better chance of coming into collision than would this planet with a stray comet. Still, what is possible may happen some time. Should such a contingency eventuate, the probabilities are that thia acrid planet would be but little incommoded by the impact, though

none can say what the effect would be upon our atmosphere or upon the life which depends upon it.