Space Exploration Timeline

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Feb 22, 1966
  –  

Soviet space dogs, Veterok and Ugolyok were launched to spent 21 days in orbit

Veterok (Ветерок, "light breeze") and Ugolyok (Уголёк, "ember") were launched on 22 February 1966 on board Cosmos 110, and spent 21 days in orbit before landing on 16 March. This spaceflight of record-breaking duration was not surpassed by humans until Soyuz 11 in June 1971 and still stands as the longest space flight by dogs. The two dogs showed signs of "cardiovascular deconditioning" with dehydration, weight loss, loss of muscle and coordination and took several weeks to fully recover, though they showed no long-term issues.

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