BEYOND NEPTUNE.

Hokitika Guardian, 16 August 1924, Page 1

BEYOND NEPTUNE.

IS Til Ell E A i’LANET. The possibility of the existence of an additional planet in the solar system, beyond the orbit ol Neptune, i.s a speculation which lias engaged the attention of astonotners for many years. Neptune, the most distant planet, although observed by I.alamle in 17115, ■was not positively identified until 1810. and its discovery came about as the result of investigations which were made to account for irregularities that had been observed in the behaviour of the planet Uranus, discoveted by Sir William Herseliel in liSl. In the case of Neptune, however, it will he many years before it will indicate whether there are irregularities in its movement, and it will he 12125 A.D. before the planet will have completed two revolutions round the suit since it, first observation. Nevertheless, there arc other factors which may afford very valuable indications. Each of the four major planets—Jupiter. Saturn. Uranus, and Neptune is known to have a family of comets; that is to say, certain points in the orbits of these planets coincide with the aphelion of certain comets. Jupiter lms a large family of comets. including Encke’s comet, whit'li lias the sliorest period of any known comet, namely :!j years. Neptune Inis six c omets, of w hich f lie most famous is Halley’s. There are other comets which appear to he periodic. whose' aphelions are more remotely situated. Two comets of the last century, for instance, suggest the distance of a hypothetical planet from the sun. Comet 111, of 1802 and comet 111. of 180!), the lirst of which i> associated with what are known as (lie August meteors, have aphelion distances pointing to the existence ol a I lanet tit about -1,105.0(10.000 miles from the suit, the distance of Neptune trout the stilt being about 2,700X00.000 miles.

A number of attempts have been made to adduce hv means of calculations the supposed till ra-Nept mini planet. The Inhnriniis and complicated computations of the two distinguished mathematicians, Adams ami l.cvorrier. who wore responsible for the discovery of Neptune, have been avoided by the adoption of a graphical process aided hv more simple computations, t Iti* subject has recently received the attention of I’t'nlossor 11. \\ . Dickering. Hit' well-known astronomer, who has deduced the elements of a hypothetical planet. Taking the epoch as the year 1!)2H, he hits placed the position of the hotly .as follows: Longitude 07.8 degrees, right ascension (i hours ill minutes, declination north 2-1 degrees. 'I In* mean distance of the 1 lanet frctii the sun would he 55.1 times the distant e between the earth ami sun. or about sl.lß7.C!Mh('iO(> miles. Its period is calculated at -I0!> years; tints two of its revolutions (SIS years) would he nearly eiptal to live revolutions of Neptune (*‘2l veals). Compared with the mass of the major planets, the hypothetical body would be quit g small, it ltd its inn-s i, estimated to he about- (who that of the earth. Thus if its tleii-s-itv were ."tual to that of the vn ft It. its diameter Would he a little short o) 10.(!:;0 mile-. Neptune, however, v. hi’ lt is 55 times the volume <>T the earth, .although its density is only about one-third of our planet, litis a diametei of about 2!).f!<)!> miles. Vet Neptune I- invisible to the naked eve, bring chis-ed as att eighth magnitude chit c-t; so that the liypntlictii al body. rc-ially as it would have only the relic id light of the sun. would ha very small indeed. It would, in cot. • iji] rat- as a 15th. magnitude star, ami tints its discovery nitty only hi* made l.v mcatis of a.-troicomical pliotogr:t| by. fciwiri«r.wv mcm