Cosmonaut Valentina Tereshkova became the first woman in space.
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The Soviet Union's Vega 1 Space Probe began sending back images of Halley's Comet.
Radiation from an explosion on the magnetar SGR 1806-20 reached Earth.
German Astronomer Karl Ludwig Harding discovered the 3 Juno asteroid in the Asteroid Belt.
Jupiter's moon was found to have a liquid ocean under a thick crust of ice.
Carolyn & Eugene Shoemaker and David Levy discovered the Shoemaker-Levy 9 comet.
