Mary Struble, Age 11, of east Brunswick, N.J., for her question:
What does the aurora look like?
The Roman writer Seneca described the aurora almost 2,000 years ago. To him, it was like fiery flames in the sky. The light, he noted, was sometimes still and sometimes full of movement. He saw vivid reds in the aurora, white and yellow, a variety of scintillating colors and a pale light he compared to a faint and dying flame.
The aurora may be a ghostly glimmer, low above the northern horizon. It may be a breathtaking spectacle of shimmering colors spread over the whole sky. The display is centered in the north. It may last all night though as a rule it is at its best before midnight.
The light of the aurora is a pale wash of colors, usually too gauzy to hide the twinkling stars. The ghostly glow may pulse silently over the sky, now brighter, now dimmer. Sometimes for a while it remains still. The aurora is most often tinted with palest apple green. But it may throb with gauzy veils of rosy pink, pearly gray and pastel tints of Violet. The scintillating colors may settle down to a tissue thin sheet of palest yellow. Nearer the polar regions, the aurora is often fiery red.
The aurora we see most often looks like an arch of filmy light in the northern sky. The outer edge of the arch may be fringed with shimmering rays, piercing the sky like flickering darts. We also may see a curtained aurora. This glimmering vision may cover the whole sky like waving draperies, now hanging in quiet folds, now billowing in the breeze.
The corona aurora is very rare. It is a gigantic display, dancing over the sky like a merry fiesta. Dozens of gauzy ribbons and streamers run up to meet and then fan out in dizzy spirals across the heavens. In polar regions, the aurora may sit on the horizon like a sunburst of darting, ruby red flames.
In the IGY, both the Northern and Southern Lights were observed from stations around the world. The scattered information was assembled to get a global picture of each display. An observer from one spot sees only a small section of a total aurora which may loop thousands of miles through the upper atmosphere.
A magnificent auroral display appeared on June 30, 1957, as if to greet tile opening of the IGY. From New Jersey, one might have seen a glimmering glow in the northern sky.. But reports from far and wide showed that this aurora spanned the whole continent in two gigantic arcs. One kept close to the Canadian border. The other arc swooped from San Francisco to Texas and up to the Carolinas.