Fifteen years ago today — July 18, 1994 — fragment G of comet Shoemaker-Levy 9 comet hit the planet Jupiter. Pieces of the comet had started impacting the gas giant on July 16, and continued to bombard it until July 22.
(Hubble Space Telescope images of the Shoemaker-Levy “Fragment G” impact. The bottom image shows the plume about 5 minutes after impact on July 18, 1994, and the next shows the “fresh impact site” about 90 minutes later. The upper images show the evolution of the impact area over the next few days due to Jupiter’s winds. NASA image from http://www2.jpl.nasa.gov/sl9/hst.html.)
In other space history, which I didn’t post yesterday because it was a crazy busy day:
Eighty years ago yesterday — July 17, 1929 — Dr. Robert Goddard launched a liquid-fueled rocked in Auburn, Massachusetts. The vehicle carried a small camera, a thermometer, and a barometer, and actually generated publicity about a possible “moon rocket.”
It only took forty years before men were on their way to the moon on the same date. Pity that we haven’t made similar progress since.
And 25 years ago yesterday — July 17, 1984 — Soyuz T-12 launched from the Baikonur Cosmodrome to carry Vladimir A. Dzhanibekov, Svetlana Y. Savitskaya, and Igor P. Volk to the Salyut 7 space station. A few days later, Savitskaya would become the first woman to conduct a spacewalk.
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