IGO Notes to the Extra Observations of Magnetometers, November 24 — December 31, 1844. 



NOTES ON THE AURORA BOREALES. 



6. 



Band of cirrus to east, lying nearly S by W. and N by E. ? 



.5. 



25. 



30. 



35. 



Dec. 31 15 10. 



Star shot from near zenith to NNE. 

 Faint auroral light to north ? 



Faint auroral light to NNW. ; a shooting-star to north at 7'' 58™ moving northwestwards. 11'' 5™. 

 Auroral light to NNW. 25™. Auroral light becoming fainter. 40™. Auroral light very faint. 



(Sunday evenino-.) Brilliant aurora seen by me first at this time, it had been seen sometime before 

 by Mr Hoo-cf, and shortly before by Mr Welsh. At 10'' Mr W. conceived the centre of the auroral 

 arch' to be nearly nortli. 



The only clouds were to north, almost covering the aurora ; they stretched in a scries of belts or arches 

 from about WNW. to E. The extremity to east had a sort of cycloidal rise, similar to what I have 

 before observed in auroral arches. 



The moon apparently rising due east; at an altitude of about 15° above it, and at the edge of the cir- 

 rous clouds, sprinc a series of streamers lying en echelon, they reach about as far as 45" above the 

 SE. At some times it was imagined that the streamers were seen beloiv the cirrous cloud, but as 

 the cloud was thin the streamers were probably only seen through it. 



The streamers rising from the east, where the moon has now risen, are inclined at an angle of about 

 30° to the south of the prime vertical ; they are seen as far as the meridian, where the streamer is 

 joined by another rising from the SW. These streamers are at times in patches, pulsating and 

 variable ; those rising from east have now a more compact form. 



Faint auroral patches to SW. variable. 

 40-45. The patches to SW., nearly radiate from that point, are varying in size and brightness, with occa- 

 sional rapid pulsations ; ultimately they took positions nearly horizontal, slightly (10° — 20°) above 

 the south point of horizon, but still pointing to about SW. In this position they were observed till 

 after 11'', and were nearly stationary ; indeed, had they not been closely watched during the whole 

 period they would undoubtedly noiu have been taken for nebulous patches of cirri lighted by the 

 moon. It is necessary to be particular on this point, as I have frequently seen similar appearances 

 in which I could have no confidence as to whether they were auroral or not. In this case, however, 

 they were seen from their formation varying in brightness and form with, rarely, rapid pulsations, 

 until they were nearly stationary to south, without any auroral changes, although sliijht changes in 

 position were observed after a considerable watching. 



About 40"" the streamers to east became one bright pencil, moving slightly to south, its origin now 

 pointing E J S., and the highest point bent like a hook to south. 

 40-45. Two very bright falling stars seen to west, one moving from about 40° altitude west to about 20 

 altitude W by N., direction nearly to WNW ; the other moving from about 70° altitude W by N. 

 to 50° ? altitude WSW., motion about SW. 

 50. Fallincr star to south, 4-5° altitude, moving S. by E. among the streaks of aurora. 



About 45"* pencils were seen rising from WNW. portion of the north arch, which was nearly all covered 

 by cloud as before mentioned; bright specks could, however, be seen occasionally to NNE., and the 

 extremity of the arch at WNW. was always seen. 



It should be mentioned, that it was conceived that the aurora was always brighter to SW. than to 

 the S. or WSW. 

 13 10. Patches of thin cirro-stratus, chiefly to east. Thin haze or cirri above, caiusing a small lunar corona. 

 Aurora faint, probably from the moonlight. Bright patches near north horizon. Nebulous streaks 

 and patches over the sky, which mat/ be auroral, but the moonlight renders it doubtful ; about 12'' 

 patches or streaks were seen, having a strong resemblance to those seen previously to south. 

 Auroral light very faint to north. 



The aurora was observed by several persons before 8'' Gottingen, and was, according to them, very 

 brilliant. Mr Welsh thought at 6'' Gottingen that there was an appearance of aui'ora to north, but 

 conceived it might be a tivilight-effect. 

 The sky looks more milky to north than on other points. Aurora ? 



35. 



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