Early space researchers were concerned about the perils of space flight. Before humans actually traveled into space, there were theories that humans might not be able to survive long periods of weightlessness. The scientific community had serious debates about its affect on humans, so US and Russian scientists used animals - mainly monkeys, chimps and dogs - in order to test their ability to launch a living organism into space and bring it back alive and unharmed.

On June 11, 1948, a V-2 Blossom launched into space from White Sands, New Mexico carrying the first monkey astronaut, Albert I, a rhesus monkey. He flew to over 63 km (39 miles), but died of suffocation during the flight. Lack of fanfare and documentation made Albert an unsung hero of animal astronauts. Three days later, a second V-2 flight carrying a live Air Force Aeromedical Laboratory monkey, Albert II, attained an altitude of 83 miles (technically making him the first monkey in space). While he survived the flight, he died on impact.

An unanaesthetized mouse was launched in another V-2 on August 31, 1948. The mouse was photographed in flight and survived the impact. The third V2 monkey flight, carrying Albert III (a cynomolgus monkey) launched on September 16, 1949. He died when his rocket exploded at 35,000 feet. On December 12, 1949, the last V-2 monkey flight was launched at White Sands. Albert IV, a rhesus monkey attached to monitoring instruments, was the payload. It was a successful flight, reaching 130.6 km., with no ill effects on the monkey until impact, when it died. In May 1950, the last of the five Aeromedical Laboratory V-2 launches (known as the Albert Series) carried a mouse that was photographed in flight and survived impact.

The following year in September, Yorick, a monkey, and 11 mice crewmates were recovered after an Aerobee missile flight of 236,000 feet at Holloman Air Force Base, New Mexico. Yorick enjoyed a bit of fame as the press covered the first monkey to live through a space flight. The next May, two Philippine monkeys, Patricia and Mike, were enclosed in an Aerobee nose section at Holloman Air Force Base. Researchers placed Patricia in a seated position while her partner Mike was prone, to test the differences during rapid acceleration. Keeping the monkeys company were two white mice, Mildred and Albert, inside a slowly rotating drum. Fired 36 miles up at a speed of 2000 mph, the two monkeys were the first primates to reach such a high altitude. The capsule was recovered safely by descending with a parachute. Both monkeys moved to the both at the National Zoological Park in Washington, DC and eventually died of natural causes, Patricia two years later and Mike in 1967.

Meanwhile the USSR was watching these experiments with interest. When they started experiments with living creatures, they primarily worked with dogs.

The year after the USSR launched Laika, the dog, into space, the US flew Gordo, a squirrel monkey, 600 miles high in a Jupiter rocket. As later human astronauts would, Gordo splashed down in the Atlantic ocean. Unfortunately, while signals on his respiration and heartbeat proved humans could withstand a similar trip, a flotation mechanism failed and his capsule was never found in the Atlantic Ocean.

On May 28 of that year (1959), Able, an American-born rhesus monkey, and Baker, a South American squirrel monkey launched in the nose cone of an Army Jupiter missile. They rose to an altitude of 300 miles and were recovered unharmed. Unfortunately, Able did not live very long as she died from complications of surgery to remove an electrode on June 1. Baker lived happily until he died of kidney failure in 1984 at the age of 27.

Later that year saw the launch of one of the most famous space monkeys. Sam, a rhesus monkey who got his name from the Air Force School of Aviation Medicine, launched on December 4 in a cylindrical capsule within the Mercury spacecraft atop a Little Joe rocket in order to test the launch escape system (LES). Approximately one minute into the flight, traveling at a speed of 3685 mph, the Mercury capsule aborted from the Little Joe launch vehicle. After attaining an altitude of 51 miles, the spacecraft landed safely in the Atlantic Ocean. Sam was recovered, several hours later, with no ill effects from his journey. He was later returned to the colony in which he trained, where he died in November 1982 and his remains were cremated.

Sam's mate, Miss Sam , another rhesus monkey, was launched on January 21, 1960, for another test of the LES. The Mercury capsule attained a velocity of 1800 mph and an altitude of 9 miles. After landing in the Atlantic Ocean 10.8 miles downrange from the launch site, Miss Sam was also retrieved in overall good condition. She was also returned to her training colony until her death on an unknown date.

It wasn't until January 31, 1961 the the first of the space chimps was launched. Ham, whose name was an acronym for Holloman Aero Med, became the first chimp (chimpanzee) in space. Ham went up aboard the Mercury Redstone rocket on a sub-orbital flight very similar to Alan Shepard's. Brought from the French Camaroons, West Africa, Ham was born July 1957. When he arrived at Holloman Air Force Base in New Mexico in 1959, the original flight plan called for an altitude of 115 miles and speeds ranging up to 4400 mph. Due to technical problems, however, the spacecraft carrying Ham reached an altitude of 157 miles and a speed of 5857 mph and landed 422 miles downrange rather than the anticipated 290 miles.

Ham performed well during his flight and splashed down in the Atlantic Ocean 60 miles from the recovery ship. He experienced a total of 6.6 minutes of weightlessness during a 16.5-minute flight. A post-flight medical examination found Ham to be slightly fatigued and dehydrated, but in good shape otherwise. Ham's mission paved the way for the successful launch of America's first human astronaut, Alan B. Shepard, Jr., on May 5, 1961. Upon the completion of a thorough medical examination, Ham was placed on display at the Washington Zoo in 1963 where he lived alone until September 25, 1980. He then was moved to the North Carolina Zoological Park in Asheboro. Upon his death on January 17, 1983, Ham's body was preserved and loaned by the Smithsonian Institution to the International Space Hall of Fame in Alamogordo, New Mexico.

The next primate launch was a disaster. Goliath, a one-and-a-half-pound squirrel monkey, was launched in an Air Force Atlas E rocket on November 10, 1961. The SPURT (Small Primate Unrestrained Test) monkey was killed when the rocket was destroyed 35 seconds after launch from Cape Canaveral.

The next of the space chimps was Enos. Enos orbit the earth on November 29, 1961, aboard a Mercury Atlas rocket. Originally he was supposed to orbit the Earth 3 times, but due to a malfunctioning thruster and other technical difficulties, flight controllers were forced to terminate Enos' flight after two orbits. Enos landed in the recovery area and was picked up 75 minutes after splashdown. He was found to be in good overall condition and both he and the Mercury spacecraft performed well. His mission concluded the testing for a human orbital flight, achieved by John Glenn on February 20, 1962. Enos died at Holloman Air Force Base of a non-space related case of dysentery 11 months after his flight.

From 1973 to 1996, Russia, or its predecessor, the Soviet Union, launched a series of life sciences satellites called Bion. Research partners have included Austria, Bulgaria, Canada, China, the Commonwealth of Independent States, Czechoslovakia, East Germany, the European Space Agency, France, Germany, Hungary, Lithuania, Poland, Romania, Ukraine, and the United States. The Bion spacecraft is a modified Vostok type and is launched on a Soyuz rocket from the Plesetsk Kosmodrome in northern Russia.

Bion missions are typically put under the Kosmos umbrella name, used for a variety of different satellites including spy satellites. The first Bion launch was Kosmos 605 launched on October 31, 1973. The satellite carried tortoises, rats, insects, and fungi on a 22-day mission. Other missions have also carried plants, mold, quail eggs, fish, newts, frogs, cells, and seeds.

Starting with Bion 6 (Kosmos 1514), these missions have carried pairs of monkeys. Bion 6/Kosmos 1514 was launched December 14, 1983, and carried the monkeys Abrek and Bion on a five-day flight. Bion 7/Kosmos 1667 was launched July 10, 1985 and carried the monkeys Verny ("Faithful") and Gordy ("Proud") on a seven-day flight. Bion 8/Kosmos 1887 was launched September 29, 1987, and carried the monkeys Yerosha ("Drowsy") and Dryoma ("Shaggy") on a 13-day flight. Yerosha partially freed himself from his restraints and explored his orbital cage during the mission. On reentry, Bion 8 missed its touchdown point by 1850 miles, resulting in the death of several fish on board due to the frigid weather. Bion 9/Kosmos 2044 was launched September 15, 1989, and carried the monkeys Zhakonya and Zabiyaka ("Troublemaker") on a 14-day flight. Temperature problems onboard resulted in the loss of ant and earthworm experiments.

Bion 10/Kosmos 2229 was launched December 29, 1992, and carried the monkeys Krosh ("Tiny") and Ivasha on a 12-day flight. Bion 10 was recovered two days early due to thermal control problems that resulted in unacceptably high onboard temperatures. Seven of fifteen tadpoles onboard died as a result of the high temperatures. Both monkeys were treated for dehydration and recovered. One monkey also suffered weight loss when he went without food for three days. Bion 11 was launched December 24, 1996, and carried the monkeys Lapik and Multik ("Cartoon") on a 14-day flight. Tragically, Multik died the day after the capsule recovery during his post-landing medical operation and checkup.

Multik's death raised new questions regarding the ethics of using animals for research. NASA dropped out of participation in a planned Bion 12 mission. Although NASA continues biological experiments aboard space shuttle and ISS missions, there have been no more primate (space chimps) missions.