What Solar Eclipses Have Taught Us About the Universe

Total solar eclipses like the one that will cross the U.S. on Aug. 21 have captured the attention of astronomers throughout history — and have often led to advances in our understanding of how the universe works. Astronomers have been studying solar eclipses for centuries. In the late 16th and early 17th centuries, Danish astronomer Tycho Brahe and his apprentice German astronomer Johannes Kepler studied eclipses to try to arrive at a rough estimate of the moon’s diameter. In the 19th century, eclipse observations got even more interesting, thanks in large part to advances in scientific instruments like telescopes and spectrometers, devices that let scientists analyze the chemistry of stars and distant planets. In 1868, French astronomer Jules Janssen and English astronomer Norman Lockyer were observing separate solar eclipses when they discovered a new element, which they named helios, after the Greek word for “sun.” Today, it’s known as helium. During an eclipse in 1879, American astronomer Charles Augustus Young and Scotland-born astronomer William Harkness both thought they had discovered another new element. But they had actually observed exceptionally hot iron in the sun’s corona, the sun’s outer atmosphere. This was the first indication that the corona is millions of degrees hotter than the sun’s surface, a mystery that puzzles astronomers to this day. Perhaps the most interesting eclipse-based discovery came in 1919. Al...
Source: TIME.com: Top Science and Health Stories - Category: Consumer Health News Authors: Tags: Uncategorized eclipse Science space space 2017 time original time video universe vintage space Source Type: news