NEW STAR IN THE CONSTELLATION AURIGA. 57 



Further Remarks on Nova Aurigce. By Professor Ralph Copeland. 



(Communicated 21st March 1892.) 



The most remarkable additional fact that I have to communicate is a sudden diminu- 

 tion in brightness that seems to have set in about the 7th of March. Throughout the 

 month of February the Nova exhibited continual and irregular changes of brightness, 

 which are shown by the dots in the diagram. The state of the sky was unusually 

 favourable during the earlier part of February, and later on still offered occasional 

 opportunities of comparing the star with its neighbours. Unfortunately, on March 8, 

 I had the misfortune to lose the very fine binocular that had up to that time been used 

 in these observations. Hoping that it might be recovered, and not apprehending that 

 any very surprising change in the star's brightness was about to occur, I did not attempt 

 to replace it until the 13th, when, on examining the heavens with a good opera-glass, I 

 was unable to identify the star. It was, however, readily found with a 35-inch refractor, 

 but had declined to the 8*6 magnitude. [See figure 3, and the table on p. 58.] On the 

 19th it had lost a further ,m 3, while last night it had so far faded as only to be of the 

 9"1 magnitude. We thus see that on February 7 the Nova was about 132 times as 

 bright as it was last night. Its brightness on the 8th and 20th are in the ratio of 14 

 to 1. 



Last night, March 20, Nova being about one magnitude brighter than the small star 

 close to it, which was observed at Bonn 34 years ago, it was still practicable to analyse 

 its light with the small spectroscope. The spectrum was strongly continuous in the 

 yellow, green, and blue, with several intenser parts that probably represented bright lines. 

 No trace of the bright C line, formerly so conspicuous, could be made out. It does not 

 seem, at present, that the spectrum is likely to become reduced to a single bright line as 

 was the case with the Nova of 1876, but it seems rather to resemble the continuous 

 spectrum of Nova Coronse, as it appeared in 1866, when the bright lines were superposed 

 on the continuous spectrum. 



Note added April 17. 



The further history of this star, as seen in the Edinburgh reflector, is one of steady 

 and continued decline. The magnitudes on the days of observation are given below 

 until April 1, when it was seen for the last time. The place was examined in a hazy 

 sky on April 14, and again on the 18th, when the night was clear, with the exception 

 of a little inevitable smoke ; on neither of these occasions was a trace of the star dis- 

 cernible. Its spectrum was " continuous with traces of dots " on March 25, the star being 

 estimated of the 107 magnitude. The brighter magnitudes have been apportioned in 

 accordance with the Durchmusterung and some Harvard measures. The fainter part 

 of the scale has been formed on the assumption that the " Bonn star " is 9 ,m 9, while the 



