'We can't forget about Ham': Friday marks controversial space exploration milestone

USA Today

31-01-2025

It was January 1961, and NASA was in its early years of existence. John F. Kennedy would soon declare the nation's goal of landing a man on the moon in that decade. But the country's best scientists still knew very little about what a human would go through during a trip to space, so they turned to the closest animal they could think of to test it out: chimpanzees.
Friday, Jan. 31, marks the anniversary of Ham the chimpanzee's space flight, which happened 64 years ago. Though not the first animal sent to space, Ham was the first hominid – any species including humans in the great ape category – to make it there.
Ham ‒ who was about 3-and-a-half years old at the time of the flight ‒ not only survived, but was able to carry out tasks he was trained to perform.
Previously, monkeys, mice and others had been tested on in their own space flights, including tests that ended fatally for the animals.
Ham's flight would directly pave the way for the first American to go to space just months later, astronaut Alan Shepard, and indeed eventually make to the moon in 1969. Shepard's May 5, 1961, suborbital flight was a success but Soviet Union was still the first to send a human to space, soon after Ham's trip.
Still, the chimp's contribution to space research is regarded today as a vital stepping stone in what would be extremely rapid development within the U.S. space program.
"We can't forget about Ham and how important his experience was to telling us what we needed to know to get that confidence to put a human in space and to continue on, which would ultimately lead to the success of Apollo in July of 1969," Brian Odom, NASA's chief historian, told USA TODAY.
Photos of Ham in a little space suit strapped into his space capsule or interacting with his trainers on the ground evoke awe at the lovable creature's accomplishments, but a closer look at Ham's story reveals the ordeal he went through to pave the way for Americans to send people into space.
"He didn't have a choice. His life and his ability to live freely as a chimpanzee was taken away from him," said Ana Paula Tavares, the CEO of the nonprofit Save the Chimps, which operates a sanctuary for chimpanzees in Florida. The organization was founded in the 90s when its founder, the late Dr. Carole Noon, sued the Air Force for custody of some of the chimps it used for space research.
Ham's was an "unwilling sacrifice," Save the Chimps' website says. 'They have bravely served their country. They are heroes and veterans," Noon once said of chimpanzees used in space research.
The pushback is part of a larger trend of animal rights activists who have called for an end to many kinds of testing on animals. But the practice continues in various forms such as drug research and has led to countless scientific advancements.
What to know about Ham the chimpanzee
Ham got his name from the Holloman Aero Medical Center, at the Holloman Air Force Base in New Mexico, where he underwent training. At the time of his space flight, he was estimated to be about 3-and-a-half years old. He'd been originally captured in the former French Cameroons and was purchased by the U.S. Air Force in 1959.
Ham, previously known as subject No. 65, was one of a group of dozens of chimpanzees trained and analyzed. As time got closer to launch, the group was narrowed to the healthiest and best performing chimps, and ultimately Ham was selected to make the trip.
After his space flight, Ham was sent to D.C.'s National Zoo for 17 years, where he lived alone, and was later transferred to the North Carolina Zoological Park until his death at about 26-years-old.
What was Ham's mission?
NASA used Ham to test the Mercury Redstone rocket before humans were sent into space, and to see what effects space travel could have on human bodies, as chimps were considered physiologically close. Specifically, scientists hoped to discover how the human body would be impacted by weightlessness and acceleration, and whether cognitive functioning would be impacted. This was important to understanding whether humans could carry out complex tasks on their own space trips.
Ham was trained using rewards of food and punishments of electric shocks to respond to differently colored lights by pressing on levers. During his mission, scientists wanted to see whether his response time would be impacted by the still relatively unknown demands of space travel.
"(T)hey specifically wanted a brainy animal like a chimp to see if space flight interfered with the ability to perform cognitive tasks," Larry Carbone, a veterinarian and visiting fellow at Harvard Law School's Animal Law and Policy Program, said in an email.
Ham was attached to several different sensors to monitor his heartrate, temperature and other vitals and strapped into a capsule called a "couch" that would hopefully allow him to keep breathing if pressure in the rocket failed.
There were issues with the flight, Odom said. A technical problem with a booster caused the Mercury capsule to be pushed beyond its intended altitude and landing point. According to NASA, it was supposed to reach an altitude of 115 miles and speeds up to 4,400 mph. Ham's aircraft reached an altitude of 157 miles and a speed of 5,857 mph. He experienced 6.6 minutes of weightlessness during the 16.5-minute flight.
The error caused Ham to be subjected to forces "far beyond what we would want a human to experience, 15 times the force of gravity at one point in the deceleration," Odom said.
Despite this, Ham performed his tasks well with only a slight delay during the deceleration, researchers found. He was dehydrated and exhausted when he was fished out of the ocean after landing, having spent several hours restrained in his couch. Further examination showed that he was in relatively good shape, and didn't sustain any lasting effects from the trip, Odom said.
"They feel very confident from this experience that a human will be able to survive it," Odom said.
The ethics of sending animals into orbit
Ham's ordeal has drawn scrutiny as a greater public understanding of just how similar chimpanzees are to humans has grown. The flight was before the popularization of Jane Goodall's research, which Carbone said can be credited for increased awareness of chimps as "our intelligent, sensitive cousins."
Ham was still a baby when he was sent into space, Tavares said. Had he not been captured and bought for research, he would still have been nursing at the time of his space flight, she said.
Ham was trained for over 200 hours before his flight, which included applying electric shocks to the soles of his feet when he didn't respond correctly to the lights. To monitor Ham while in orbit, a number of sensors were attached to him, including a rectal thermometer probe that was inserted about 8 inches into his rectum, according to a report published after the research. He was restrained in the couch for hours and had his sleep cut short the night before his launch. When he landed, Ham had an abrasion on his nose, was dehydrated and had lost over 5% of his body weight.
Upon landing, "what most people see and think is a smile on his face, is a grin that we all know... is an expression that chimps have when they are super stressed and terrified," Tavares said.
Later, when veterinarians tried (and failed) to put Ham back in a similar capsule in front of members of the media, "The normally cheerful chimp balked, screeched and hugged his handler's neck," the El Paso Times reported in 1961.
NASA still sometimes sends animals to space, but we won't be seeing these kinds of experiments on chimpanzees again, Odom said. That's partly because of evolving standards – chimpanzees are now listed as endangered – and because there's no longer the same need for such tests.
"I think NASA understood at the time that these tests were critical to gaining a level of confidence ... So these tests were very critical that process," Odom said.
Tavares said even Ham's retirement was inadequate; chimps are social creatures and he should have been able to live out his years with others like him. She likes to think that people didn't know better then, and said that's why it's important to remember Ham today.
"We honor and remember not only Ham, but all of the other chimpanzees and the descendants of those chimpanzees here at the sanctuary and elsewhere that sacrificed their life unwillingly, but did so for the advancement of a technology that we all benefit from to to this day," Tavares said.