In 1957, a dog became the first animal to orbit the Earth. The Soviet Union space program sent a stray dog named Laika into orbit on the satellite Sputnik II on 3 November 1957. Sputnik II orbited the Earth about 2,000 times before burning as it re-entered the Earth’s atmosphere on 4 April 1958. It initially was reported that Laika had survived aboard Sputnik II for a week, but in 2002, Dr. Dimitri Malashenkov of the Institute for Biological Problems in Moscow revealed that Laika died of overheating within hours of the launch. The launch of Laika aboard Sputnik II is thought to have made it possible for the first human, Soviet Yuri Gagarin, to enter space on 12 April 1961.
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