MELA'S COMET.

New Zealand Herald, Volume XXIX, Issue 9044, 24 November 1892, Page 6

MELA'S COMET.

M. Arago, in his lectures on Astronomy," says:—"This comet was discovered ab Johaunisberg on the 27th February, 1826, by M. Biela. M. Gambarb, who perceived it some days after at Marseilles, determined its parabolic elements, and recognised it as having been before observed in 1085 and in 1772. This is the comet that so much terrified some people, because it was forotold that it would come in collision with the earth on its return in 1832. It is true it cut the terrestrial orbit, in a point where the earth arrived a month after, but from which it was then distant more than fifty millions of miles, since at its mean speed it travels 1,873,000 miles in a day. In 1805 this comet passed ten times nearer to us, that is to say, at the distance of about five millions and a-half miles. Tho inclination of the orbit of this comet to the ecliptic is 12° 34', and it accomplishes ids course in 2410 days." The Rev. T. W. Webb says of it :■—" Singlo in all previous observed returns (those of 1772, 1805, 1826, 1832), in 1846 it became elongated, and then throw off a portion, which increased till it rivalled and even for a short time surpassed its parent, each having at one period a starry nucleus and short tail, while they were connected by faint streams of light; and thus they continued in sight for more than three months, keeping a distance of something more than 150,000 miles, tho companion being the first to vanish. When next seen by Seccbi, in 1852, bhe distance was more than eight times greater, being 2m. in R.A., and 30s. in declination, as though they were becoming independent bodies. Their next favourable return was looked for with no common interest; but they were not seen, and probably will never again be by mortal eye." The Astronomer Royal says:— " Bicla's comet was first observed in 1772, but has only been seen at six of its returns since that time. Its greatest and least distances from the sun somewhat exceed those of Jupiter and Venus respectively. Its elements, as given by Mr. Christie, are Biela: Period in years, 6*6; least distance from sun, 09 ; greatest distance, 62; long axis, 109 ; node, 246 ; tilt of orbit to ecliptic! 13; last seen, September, 1852." Jupiter appears to be a sort of watering-place for the comets, and they generally imbibe too much, for when leaving his precincts they are completely deranged, and become very erratic in their motions. Mr. Christie says Loxell's "approached the earth in 1770, within six times the distance of the moon, withoub causing bhe slightest alteration of our course, though the comet's path was much disturbed."