0 a natural appearance of coloured light in the sky, that is usually seen in the latitudes (= parts of earth) nearest the Arctic or Antarctic
It should be noted that discrete aurora and diffuse aurora are two different phenomena.
This is especially so in the aurora, where large fractional fluctuations of number density occur, together with strong electric fields.
Under a vivid aurora, with a ship lying far in the distance, some gallant naval men engaged a ferocious bear on the ice.
Its function will be to study the effects of the aurora on radio reception as part of a programme of ionospheric studies.
Scientific results of the expedition covered meteorology, oceanography, terrestrial magnetism, glaciology, physical geography, botany, geology, paleontology, ethnology and aurora observations.
He considered radiation pressure as accounting for comets, the solar corona, the aurora borealis, and zodiacal light.
Arago is also fairly entitled to be regarded as having proved the long-suspected connexion between the aurora borealis and the variations of the magnetic elements.
Energetic particles in the magnetosphere contribute to the aurora borealis and aurora australis.
