In 1921, Bengt Stromgren and a fellow student were studying stars that are close to the North Star, Polaris. They started collecting data about a half-hour after sunset, but they had to knock off by 10 o'clock -- bedtime for a 13-year-old schoolboy.
Stromgren was born 100 years ago today, the son of a professor of astronomy at the University of Copenhagen. He learned calculus by age 11, and published his first research paper at 14. In college, he studied the new discipline of quantum mechanics, which explains how the universe works on the smallest scales.
Stromgren used this knowledge to explain how stars are put together and what they're made of.
He calculated, for example, that the bulk of a star must consist of hydrogen, the lightest and simplest chemical element. At the time, most astronomers thought the interiors of stars were made of the same heavy elements that make up the interior of Earth. Stromgren also calculated the first good model of the outer layers of stars. And he calculated that hydrogen also accounts for most of the matter between stars.
By then, Stromgren was working at the Yerkes Observatory. He became director of Yerkes and McDonald observatories, which were both operated by the University of Chicago, in 1951. He kept the posts for six years. Stromgren returned home to Denmark in 1967, where he continued to make important contributions for the remaining two decades of his life.
Script by Damond Benningfield, Copyright 2007
For more skywatching tips, astronomy news, and much more, read StarDate magazine.
[3]
