In ancient China, people shot rockets at the sky during solar eclipses to scare off the "dragon" they thought was swallowing the Sun. And 50 years ago today, a U.S. Navy ship appeared to be doing the same thing. It fired five big rockets at the sky during an eclipse. It wasn't trying to scare off dragons, though. Instead, the rockets carried instruments to study the Sun's X-rays -- a form of energy that had never been studied during an eclipse because X-rays can't penetrate Earth's atmosphere.
The USS Point Defiance first dropped a team of astronomers to watch the eclipse from Puka Puka Island in the South Pacific. A few weeks later, the rest of the team headed out to sea. As the eclipse began on October 12th, 1958, the Point Defiance launched five rockets. A sixth rocket -- nicknamed "Miss Fire" -- misfired.
The rockets carried X-ray telescopes high above the atmosphere. They recorded changes in the X-ray brightness as the Moon slowly covered the Sun. They showed that most of the Sun's X-rays come from sunspots.
As the Sun disappeared behind the Moon, an X-ray glow surrounded the Moon. The glow came from the corona -- the Sun's faint outer atmosphere. The observations showed that the corona is far hotter than the Sun's surface.
Miss Fire was launched the next day. As luck would have it, a solar flare was erupting -- a brilliant source of X-rays. So the rockets scared up a lot of new information about the Sun.
Script by Damond Benningfield, Copyright 2008
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