Nelson says that the Soviets did consider using primates, particularly monkeys. They visited the circus and asked monkey handlers how the animals might fare in a rocket launch. “And they’re like, ‘No, they’re way too high-strung, they’re temperamental, they’ll succumb to the stress of the experiment,’” Nelson says.
In both countries, the training for the animals was intense, according to Animals in Space, a comprehensive history by Colin Burgess and Chris Dubbs, and might be labeled animal abuse today. The Soviet dogs were restrained in small containers for hours to simulate the confinement of spaceflight. They were exposed to loud banging noises and spun around in centrifuges to mimic the extremes of spaceflight, from launch to landing. On the American side, primates were subjected to similar shakes and sounds, on top of their motor-skills training.
The Americans began their test flights in 1948 with rhesus macaques. The first six died of suffocation, explosions in flight, or upon impact. Britz says the chimpanzees who flew in the early 1960s fared better. He remembers seeing Ham, the first chimp in space, after he was recovered from a successful flight to the boundary where space begins. “He was in such mint condition,” Britz said of Ham, who went on to live in zoos until his death in 1983. Enos, the second and last chimp to fly, survived the journey but died several months later of a bacterial infection that Britz said was unrelated to spaceflight.
The memory of the Soviet space dogs lives on today in a menagerie of merchandise, from T-shirts to nesting dolls, a legacy that glosses over a less charming reality. Laika, the first dog to go beyond the edge of space and complete an orbit of Earth, breathed frantically during launch, her heart racing at triple the normal speed. The Soviets didn’t design the mission for a safe return, and Laika died in space not long after launch, from the excessive heat in the capsule, in 1958.
“The Russians felt very badly about it, especially about Laika,” says Cathy Lewis, a curator in the space-history department at the Smithsonian National Air and Space Museum. “The principal investigator, Oleg Gazenko, who sent Laika up into space, and knowing full well that she was not going to return—before he died, [he said] that was the one thing in his career that he had really regretted.” Before the flight, Gazenko had brought Laika home with him to play with his children, Lewis says.
Read: The Soviet space program was not woke
The Soviet Union stopped launching dogs in the 1960s. The United States ended its primate program around then, too, save for two squirrel monkeys who joined astronauts on a Space Shuttle flight in 1985 (and survived). Britz says the Holloman facility had trained enough chimps for nearly every Mercury astronaut; Ham had been a test run for Shepard, and Enos for John Glenn, the first American to orbit the planet. After Glenn flew and reported that the experience of weightlessness was, actually, “extremely pleasant,” the chimp program was canceled.