National Geographic : 1989 Nov
NOVEMBER 1989 GEOGRAPHIC NATIONA GEORAPI AGAZsINESnv e DAVID C. FRITTS Red-tinged Auroras To Be Remembered In the far north the aurora borealis, or northern dawn, illuminates night skies with ever changing green and-white light shows. But last winter's magnificent displays also bore tinges of red, a tint that rarely appears, and could be seen as far south as Florida. The aurora borealis and its southern counterpart, the aurora australis, oc cur when sunspots or solar flares send electrically charged particles cascading into space. When they encounter the magnetic "envelope" around our plan et, they are funneled to the areas around the poles. There the particles collide with atoms and molecules in the earth's upper atmosphere, emitting light. Although this happens at all times of the year, auroras are best seen during winter's long, dark polar nights. Last winter's unusually intense dis plays and rare coloring were caused by the approach of a "solar maximum," a phenomenon that occurs about every 11 years. On such occasions, sunspots, gaseous eruptions, and emissions of electrically charged particles reach a peak. The 1988-89 auroras were the most spectacular since 1957-58, says David Fritts of the Geophysical Insti tute of the University of Alaska, who was skiing on the Canwell Glacier in the Alaska Range and photographed the nightly displays (above). Auroras this coming winter and the following winter as well-the years of the solar maximum-should be espe cially frequent and dramatic. Florida Law Dictates Respect for the Past The agonizing question of how to deal with prehistoric Native American burial sites (NATIONAL GEOGRAPHIC, March 1989) has resur faced, in Florida. But this time a new state law provided guidelines. Workers building a house on Mana sota Key, on the southwestern coast, uncovered human bones late last year. Authorities determined that they were prehistoric and that no criminal investi gation was needed. But the state tem porarily halted construction under a new law designed to insure that re mains are treated respectfully. Meanwhile, Wilburn A. (Sonny) NITAEDMONDSON Cockrell, a Florida State University archaeologist, organized a team that began a systematic excavation. The site, which dates from A.D. 120 to 320, yielded about a hundred burials; 66 skeletons were recovered intact. Cock rell (left) thinks the site was both a sea sonal camp, where mainland Indians came to gather food, and a cemetery. "Ancient cemeteries from this time period, as opposed to isolated burial mounds, were previously unknown to the area," he says. Members of two Florida Indian tribes visited the site to make sure that the bones were treated properly. Under the law a committee that in cludes two Indians will advise the state archaeologist on what to do with the remains after they have been analyzed.