Word: sun
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Dates: during 1980-1989
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...great flare, and its coterie of sunspots, was an unmistakable signal. It heralded the imminent arrival of the solar maximum: the period every eleven years or so when the sun reaches its peak levels of activity and pointedly reminds earth dwellers of its awesome power. At maximum, the sun...
During a maximum, marked by a jump in the number of sunspots and flares, giant loops of incandescent gases, called prominences, proliferate, shooting tens of thousands of miles above the solar surface, sometimes hanging suspended for months. The solar corona, the halo around the sun visible during total eclipses, becomes fuller and brighter; great blobs of the corona, containing billions of tons of hot gas, occasionally burst free, shooting into space at speeds as high as 2 million m.p.h. And the earth's upper atmosphere, pummeled by solar particles, is laced by electrical currents of as much as a million...
Because the previous maximum occurred in late 1979, astronomers had targeted 1991 as the year when solar frenzy would again peak. But the sun is notably capricious. While the intervals between maximums average eleven years, some have been as short as seven, others as long as 17. Ever since the sun began revving up three years ago toward the next maximum, its activity has mounted with unprecedented speed...
FOOTNOTE: *The sun flared into life around 4.5 billion years...
...fireworks, astronomers scheduled a two-week, worldwide solar-observation period during the second half of June. The project was timed to benefit from the observations of the Solar Maximum Mission satellite (nicknamed Solar Max) before it plunges to its death. Lofted into earth orbit in 1980 to monitor the sun's activity, the satellite is gradually descending and will probably re-enter the earth's atmosphere in November and be incinerated. Solar Max's readings of the sun's activity were coordinated with observations made all over the world by ground-based telescopes and instruments mounted on high-flying rockets...