Relationships of the Aurora.

Harper's new monthly magazine, 41 / 1870

A recent article by Mr. Proctor, upon the aurora, may be summed up as follows: First, the increase and diminution of the disturbance of the magnetic needle corresponds, in periods of about ten years, with the increase and diminution of the number of solar spots; secondly, the auroral displays announced as seen from all parts of the earth probably correspond to similar manifestations upon every planet; third, the spectrum of the aurora exhibits only a single bright line, and hence it is due to luminous vibrations, the luminosity being caused by the passage through it of electrical discharges; fourth, the same bright line is exhibited by the spectrum of the zodiacal light, by the sun's corona as seen during a total eclipse, and very faintly by the peculiar phosphorescent light sometimes seen over the whole sky. Finally, he concludes that the key to these phenomena probably lies in the existence of myriads of meteoric bodies, traveling separately or in systems around the sun.