The trailblazing animals who led the way for human spaceflight.
Since the dawn of spaceflight in the 1940s, animals have led the way.
Scientists relied on the crucial data gathered by these 'animal astronauts' to determine the biological limits of space travel.
So, it's fair to say that there would never have been a man on the moon without some of these animal explorers.
We have our problems with them, but bugs and humans inhabit many of the same places. Which is why some of the first creatures to ride a rocket were fruit flies.
With their basic anatomy and short life span, scientists used the fruit flies to answer common questions about the upper level of the Earth's atmosphere and its potential effect on humans.
After World War II, the United States took possession of the remaining stockpile of German V2 rockets. By 1947, the American military was testing the boundaries of space with the V2s and high-altitude balloons--often filled with fruit flies.
With their similarities to humans, monkeys have long played a key role in testing space vehicles.
In 1949, the United States launched a rhesus monkey, Albert II, into space.
Like many early animal astronauts, Albert II did not survive re-entry.
However, as the science of spaceflight advanced, more monkeys returned alive and well.
Miss Baker, a squirrel monkey, survived a 16-minute flight in 1959 that reached an altitude of 360 miles. The capsule landed safely, and Baker lived another 25 years.
In the 1950s, the Soviet space program led the way. And as early as 1951, the Soviets secured a series of space firsts--with dogs.
In 1951, two dogs, Tsygan and Dezik, became the first advanced animals to survive spaceflight.
Sadly, the Soviets made few provisions for Laika's survival, and she died, likely within hours of the launch due to overheating, and months before the capsule burned up on re-entry.
Three months before Alan Shepard became the first American in space, Ham the chimpanzee rode a similar Redstone rocket into space.
During his flight, Ham tested a primate's ability to perform tasks in sub-orbital space (he was trained to move levers to get food).
NASA was pleased with the results. By the end of the year, another chimp, Enos, completed several orbits of the Earth. The flight served as the final tune-up before John Glenn's orbital flight in February 1962.
Rodents have long been a favorite for scientists. So much so that to be a 'guinea pig' is slang for 'the first to try something'.
However, primates were of more interest during the early years of spaceflight. Yet, as space travel evolved, rodents once again became a favorite for scientific experiments.
During the shuttle missions of the 1980s and 1990s, mice, rats, and guinea pigs were frequently aboard and the subject of numerous experiments.
In more recent years, SpaceX flights have delivered mice to the ISS for scientific study on the effects of weightlessness and long-term space habitation.
Featured Image via NASA/Marshall Space Flight Center, Public domain, via Wikimedia Commons