Space Exploration Timeline

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Sputnik 2 sattelite

Nov 3, 1957 2:30 – Circa Apr 14, 1958 2:00

Sputnik 2 (Russian: Спутник-2, Satellite 2), or Prosteyshiy Sputnik 2 (PS-2, Russian: Простейший Спутник 2, Simplest Satellite 2),  launched on 3 November 1957, was the second spacecraft launched into Earth orbit, and the first to carry an animal into orbit, a Soviet space dog named Laika.

https://en.wikipedia.org/wiki/Sputnik_2

Includes events (3):
Nov 3, 1957 2:30
Sputnik 2 launch. First mammal in orbit, the dog Laika.
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Jan 31, 1958
Confirmed existence of the Van Allen radiation belt
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Circa Apr 14, 1958 2:00
Sputnik 2 decay
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