KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 60. N:Q 8. 



55 



After the systematic errors have been applied, 

 the observations show a relatively good concordance, 

 and the light-curve derived from the means in fig. 8 

 may be considered as a comparatively exact one up 

 to the 1 Dec. 1885. The observations obtained after 

 that time are sporadic and, owing to the low magni- 

 tudes of the stars, uncertain, and possibly have not 

 been corrected with accuracy for systematic errors. 



From the light-curve we conclude that the Nova 

 Andromedse must with regard to light-fluctuations be 

 considered as having been a typical nova. The magni- 

 tude variations of short periods, which are to be 

 seen in the curve, very much resemble the varations 

 in the light-curves of the Nova Persei, Nova Gemi- 

 norum, and Nova Aquilse. Also here there is an in- 

 dication that the period-length increases towards the 

 end of the period of observation. 



For Nova Centauri there are only 19 estima- 

 tions of magnitude known, but the light-curve drawn 

 from them seems, notwithstanding, to give the progress 

 of the variation of magnitude typical of a nova. 



From the estimations given by Ritchey for 

 the Novse Andromedse No. 5 and 6 we gather, in spite 

 of the small number of observations, that also these 

 stars will certainly have to be reckoned to the class 

 of novse. (Fig. 10). Curtis, with regard to the three 

 novse discovered by him on the Crossley reflector 

 plate3, has been able to give some data of the light- 

 fluctuations of the three stars, which, it is true, do 

 not suffice for drawing a light-curve, but, in any 

 case, for rendering it most improbable that these 

 objects should be variables of long period. 



Even if Nova Andromedse 1885 and Nova Cen- 

 tauri have, with regard to their spectra proved to dif fer 

 from the spectra of the new stars flashing up in the 

 Milky Way, yet there was no indication that the 

 former stars were to be classified among the variables 

 of long period. 



According to Curtis the value of the colour- 

 index for Ritchey's nova in N. G. C. 6946 shows 

 that this står cannot be a variable står of long pe- 

 riod, and a spectrogram of the same står, obtained 

 by Ritchey and Pease with the Mount Wilson 



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