On 3rd November 1957, a month after Sputnik 1, the Soviet Union launched the second man-made satellite into Earth orbit: Sputnik 2. It was a very different construction from its predecessor: cone-shaped, 4 metres tall and weighing 508kg, it also carried proper scientific instruments for measuring cosmic rays and particles. Its most important cargo, however, was a little dog named Laika. Laika was not the first animal to go into space – that was a collection of fruit flies, launched to an altitude of 68 miles on a V-2 missile by the United States in 1947 – but she was the first living creature to orbit the Earth, and her story is a sad one.
Following the success of Sputnik 1, Soviet premier Nikita Khrushchev wanted another satellite launched as soon as possible, to celebrate the 40th anniversary of the October Revolution. Chief designer Sergei Korolev and his engineers considered what would be both impressive and feasible in the time available, and decided to launch a satellite with a dog onboard. They already had some experience to back up this concept, having launched dogs on sub-orbital rocket flights since 1951, to test the effects of such flights on living animals. But it was known from the outset that Sputnik 2’s passenger would be going on a one-way trip: the technology to bring a satellite safely back from orbit had not yet been developed.
Three dogs received training for the flight, which involved being habituated to small spaces and put through a centrifuge to simulate the G-forces of liftoff. The chosen dog was a small mongrel who had originally been found as a stray in Moscow: she was named Laika, meaning “barker”, and was regarded as a particularly even-tempered animal. For the flight, Laika was placed inside an oxygenated cabin with just enough room to stand up or sit down, and enough food for about a week.
Following the flight, the Soviet Union officially reported that Laika had remained alive in orbit for several days, only expiring when her oxygen ran out. However, records released many years later, after the collapse of the USSR, told a different story. Sputnik 2’s environmental control system, which was supposed to keep Laika cool, failed to perform as it should, and by the fourth orbit, the temperature inside her cabin had risen to 43 degrees Centigrade. Six hours after launch, the sensors monitoring Laika’s pulse and breathing showed no signs of life; she had succumbed to heat exhaustion.
Sputnik 2 continued to orbit the Earth until 14th April 1958, whereupon it re-entered the atmosphere and was destroyed.