The Pittsburgh Press (September 19, 1941)
NORTHERN LIGHTS PRESENT AWE-INSPIRING SPECTACLE
The northern lights as seen in Bergenfield, New Jersey.
The aurora borealis – northern lights – staged one of the most brilliant displays ever seen in the United States last night while sunspots blacked out shortwave radio and interfered with land communications.
The rare and awe-inspiring spectacle was particularly bright over Pittsburgh and Western Pennsylvania, with fan-like streams of silver, green, yellow, red and blue spreading across the skies.
It halted traffic, sent thousands of persons to streets and rooftops while other thousands swamped police stations, newspapers, the Weather Bureau and the Buhl Planetarium with telephone calls.
The display – entirely unanticipated by scientists – began here about 8 p.m., and seemed to reach its greatest intensity between 9:30 and 10 p.m. However, it was visible off and on until around 4 a.m.
But the phenomenon apparently had been underway since early yesterday, although unseen until after nightfall. There is a good chance that it may be repeated within the next few days, experts said.
Some observers said the lights showed in giant beams, all focused toward a great dome overhead. The beams blinked steadily, about a second apart making what appeared to be a circle around the horizon.
Others reported that out of the streaks of white light there appeared a red ball of light which suddenly burst and created an illusion of a spreadeagle.
The lights appeared to be most brilliant in the eastern section of the country but were reported visible as far west as Helena, Mont., and as far south as Jacksonville, Fla.
Many of those who called police and newspapers seemed more alarmed than appreciative. Some of them seemed to think it was somehow connected with national defense.
Professor Kelvin Burns, of the Allegheny Observatory, said the display was undoubtedly the brightest seen here in 20 years.
While shortwave radio broadcasts were interrupted, the ordinary longwave operated with slight interference. Telephone service was not affected but telegraph transmission in an area north of the Ohio and east of the Mississippi hit.
Hits wire service
Locally, both the Western Union and Postal reported that at times yesterday and last night it was impossible to transmit messages for periods lasting from a few seconds to several minutes.
At the moment the aurora borealis made its appearance above Pittsburgh, the Buhl Planetarium was displaying a portrayal of the aurora australis – southern lights – in its Theater of the Stars.
At the end of the 8 p.m. show Dr. Arthur L. Draper, the planetarium director, stepped outside and to his astonishment saw a genuine sky show, which he commented upon at his 9 o’clock display.
Along the Atlantic Coast, many alarmed residents called the Coast Guard to find out if there were naval searchlight drills going on and some asked excitedly:
…if a German warship was about.
Calls deluge airport
At the County Airport, deluged with calls, one Weather Bureau observer patiently told a female caller that the lights in the sky were caused by the aurora borealis.
She demanded:
What’s that?
The observer replied:
Why, the northern lights.
Lights? Lights did you say? Well, who turned them on?
That’s what all of astronomers and other scientists were trying to figure out today.
The aurora borealis, they have found, followed closely the number of sunspots which are at a maximum about every 11 years.
What caught scientists unprepared for last night’s appearance of the lights is the fact that the 11-year cycle is now near its normal minimum when such a display ordinarily would least be expected.
A faintly seen aurora gives off a white light, greater brilliance gives a yellowish light and a really brilliant one shows other colors, reds, greens, purples.
Scientists have decided that the different colors are the result of electrons coming down for the upper layer of air coming in contact with rarefied gases, causing them to glow, very much like the gases in a neon sign, maybe 600 or 700 miles from the earth’s surface.
Eastern show best
While the East got the best show – lasting from a few minutes to almost two hours, many other sections also got a view of the display.
In New York, the Weather Bureau had so many calls that it finally had to switch all of them onto the automatic recorded weather forecasts obtained by dialing a certain number. This recorded report was amended to include the information that:
…the lights now visible are an unusual display of the aurora borealis.
Observers at Atlanta saw a purplish glow on the northern horizon surmounted by a pinkish arc. Some reported seeing streamers of light shooting from the horizon.
Denver reported that an aurora was visible in that vicinity early Thursday. But the Pacific Coast and southwest did not see the display. Rains hid the sky at Portland, Oregon, and Seattle, Wash., reported clouds and fog. The weather bureau at San Francisco said that the display was not visible there.
St. Louis saw lights
The weather bureau in St. Louis said that display was visible throughout the Midwest and the lights were seen in the St. Louis area from 1 a.m. to 4 a.m. today.
Albany and Memphis were two cities in the eastern part of the country which reported the lights were not seen in their vicinities.
The United Press listening post in New York was unable to hear Europe on the shortwave lengths Thursday and the radio networks reported a similar condition. NBC said its shortwave broadcasts from abroad were blacked out and that a shortwave program beamed at Mexico was not received. Television was affected also.
The sunspots interfere with solar radiations which normally maintain an ionized layer in the earth’s upper atmosphere. This layer forms a kind of mirror which reflects radio shortwaves back to earth where they are picked up by receiving sets.
Sunspots blamed
Sunspots – actual storms on the sun – tend to break up the ionized layer and the shortwaves go shooting off into space and refuse to come down.
Radio companies using long waves were not affected. The long waves travel along the surface of the earth and do not have to go bouncing around against ionized layers before they can be picked up.
Concerning the cause of an aurora, the Encyclopedia Britannica says:
It is clear that the appearance of an aurora must be closely connected with something that happens on the sun and what is seen on the earth is a mere reflex action. That it is visible at all is due to the earth itself being an immense magnet surrounded by an atmosphere.
Two theories
Since all bright shifting auroras are accompanied by magnetic storms, it seems certain that this type, and presumably all others, is caused by electrical discharges of some kind. The current evidently must come from or be induced by the sun. Two theories have been advanced. One is that the cause lies in negative particles shot off by that body and caught in the magnetic field of the earth. The second is that alpha-particles, with a plus charge, come to us from radioactive substances in the sun. In some cases at least, it has been possible to prove that only plus charges could explain the accompanying magnetic effects, but it has been pointed out that, even were these particles to move with the velocity of light, they could not penetrate the atmosphere to within a distance of 16M, from the earth’s surface.
