4 oo THE POPULAR SCIENCE MONTHLY. 



in the present year, and still visible with an opera-glass. It lies 

 about two degrees south of the star Chi Auriga?, in the Milky- 

 Way, and when first noticed was about magnitude four and a 

 half. The star seems to have been visible for some time pre- 

 viously, as it has been found that its spectrum was photographed 

 at Harvard Observatory, U. S. A., on December 1st, 10th, and 

 20th, before it was recognized as a new star. The actual time of 

 its appearance therefore remains unknown, but that it is a new 

 star there can be no doubt, as it does not appear in any star- 

 chart or catalogue. The star is a very interesting object, and, 

 according to observations by the present writer, is subject to 

 sudden changes of brightness. It seems to be fading slowly, and 

 on March 1st was still somewhat brighter than the sixth magni- 

 tude.* Its spectrum is a very remarkable one, showing, it is 

 thought, both bright and dark lines. The line C and other lines 

 in the red are visible, the D line of sodium and the series of hy- 

 drogen lines being also present. Most of the lines are said to be 

 double, each consisting of a bright and dark component. These 

 double lines suggest the presence of two bodies, or systems of 

 bodies, one approaching the eye and the other receding from it, 

 with a relative velocity of between five hundred and six hundred 

 miles per second. There is a suspicion that the bright lines char- 

 acteristic of nebular spectra are also visible. These remarkable 

 results suggest that the light of this star, and probably that of 

 all " temporary " stars, is due either to the rush of a solid body 

 through a gaseous nebula, or the clashing together of two mete- 

 oric swarms moving in opposite directions. The phenomenon 

 might also be explained by two bodies forming a binary star 

 passing through their perihelion, the great increase of light being 

 due to a " violent grazing collision " at the point of nearest ap- 

 proach. Whether this new star is a veritable nova, or " tempo- 

 rary star," or merely represents the maximum of a hitherto unrec- 

 ognized variable star of long period, like the so-called " Nova 

 Orionis," discovered by the present writer in December, 1885, 

 must be left to time to decide. In either case, it is a most inter- 

 esting object, and its future career will be followed by astrono- 

 mers with great interest. 



Coming now to Class 2, we find regular variable stars with 

 periods ranging from about 100 to 700 days, and with fluctuations 

 in their light from about one magnitude to over eight magni- 

 tudes. Among the most remarkable of these are Mira Ceti, or 

 the " wonderful star " ; Chi Cygni, already referred to ; R Hy- 



* Further observations on March 10th and 11th showed that the star had then faded to 

 below the seventh magnitude; and on March 16th I could no longer see it through an 

 opera-glass. 



