Three astronauts, Richard J. Hieb, Thomas D. Akers, and Pierre J. Thuot, simultaneously walked in space for the first time.
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NASA lost radio contact with the Mars Polar Lander moments before the spacecraft entered the Martian atmosphere.
American Astronomer William Henry Pickering discovered Phoebe, one of Saturn's moons.
The first all-female spacewalk took place.
The first spacewalk was made by the Soviet cosmonaut Georgy Grechko during Salyut 6 EO-1 mission.
Cassini orbiter released the Huygens probe, which successfully landed on Saturn's moon Titan.