Animals in orbit:

LUKE RYAN REMEMBERS THE DOGS, CATS, MONKEYS AND FRUIT FLIES THAT HUMANS HAVE SENT INTO ORBIT.

The dogs, frogs and monkeys humans have sent into space

When it comes to our ongoing battle against gravity, humans have a long and (not so) proud history of using animals as our guinea pigs – sometimes literally. Animals were the first to fly, the first to reach space, the first to orbit the Earth and the first to circle the Moon. The goals were high and the casualty rates higher, but without the brave sacrifices these creatures made, humanity never would have entered space, let alone walked on the Moon’s surface. (Although, let's just say we’re pleased to be living in a more enlightened age when it comes to the ethics of animal experimentation.)

It all started in 1783 with France's Montgolfier brothers, who had just invented the hot air balloon, but weren't entirely sure whether people could survive flying at such high altitudes. So, they conscripted a sheep, a rooster and a duck, placed them in a small basket beneath the balloon, and – while none other than Marie Antoinette looked on – let the contraption fly away into the sunset.

Spoiler: they survived. As did the fruit flies a team of Americans launched into space aboard a captured Nazi V-2 rocket 164 years later. At the time, nobody knew what effect cosmic radiation might have on humans, so the folks at New Mexico's White Sands Missile Range shot some fruit flies 100 kilometres into the air – the distance at which space officially begins – to see what happened.

While fruit flies might seem a poor equivalent for a fleshy, breathing human, among scientists they're actually a well-known surrogate: not only do we share 60 per cent of our genetic material, we also employ the same set of genes to develop into adults. So, when the flies were recovered alive, intact and suffering from no obvious mutations, it essentially gave the green light to the American space program.

But the United States needed more reassurance before they sent a person into space, so they turned their attention to our closest genetic relative: the monkey. Over the following decade, six separate monkeys named Albert sacrificed their lives to the cause. The Americans wouldn't taste success until 1959, though, when a rhesus monkey called Able and a squirrel monkey named Baker finally made it back to Earth in one piece. Their survival assuaged one of our primary fears about weightlessness – namely, that the absence of gravity would unmoor our circulatory and gastric systems and cause wholesale breakdown.

Meanwhile, the Russians had embarked upon their own animal space program. Through the 1950s, they launched a dozen stray dogs into orbit, concluding with a Samoyed-cross named Laika, who in 1957 became the first animal to orbit the Earth (and a veritable celebrity, nicknamed ‘Muttnik’ by the press). Not that Laika was around to celebrate – she sadly died a few hours into the flight due to heat stress. (An irony, as the Soviet rocket scientists had specifically chosen stray dogs because they thought they'd be well-equipped to endure extreme cold.) Three years later, the team tried again, this time packing a pair of dogs, a grey rabbit, 42 mice and a couple of rats into the Sputnik 5, sending it into orbit and landing them all safely on Earth 24 hours later.

Not to be outdone, in January 1961 the Americans dispatched a chimpanzee named Ham into space. Ham had been trained to perform tasks during the flight, like pulling levers for banana pellets, making him not only the first primate to circle the Earth and return alive, but also the first animal to actually interact with a space vessel in transit. The US victory was short-lived, though: the Russians one-upped them again just three months later by sending Yuri Gagarin, an actual human, to do the exact same thing. One would think that after a human had made it into space there would be no further need for animal experiments, but if anything, the opposite transpired. France and China got in on the action in the 1960s, sending a parade of cats, mice and rats into the ether to study the effects of microgravity on things like brain state, behavioural performance, tissue development and even doing the hanky-panky. In September 1968, the Soviet Zond 5 became the first spacecraft to orbit the Moon, an event witnessed only by two tortoises and a bunch of wine flies and mealworms. Now it was America's turn for revenge: they landed two humans on the Moon less than a year later.

In the wake of the lunar landing, our enthusiasm for sending large mammals into orbit waned. Here, after all, was definitive proof that we could survive the rigours of deep space. Focus instead turned to so-called ‘biological payloads’ – collections of amoebae, algae, insects, spiders and jellyfish that offered insight into what happens when biological matter is exposed to space for extended periods, and how that might affect the viability of building communities outside the safety of our atmosphere.

Algae, for instance, is thought to be our best option for removing carbon dioxide from the atmosphere of spaceships and off-planet settlements. In 1973, a pair of garden spiders named Arabella and Anita became a test case in animal adaptability when they spent 53 days in space on NASA'S Skylab satellite, teaching themselves how to spin webs in zero gravity. In 1988, NASA sent up a bunch of fertilised frog eggs and were pleasantly surprised when they hatched into healthy tadpoles; meanwhile, live bullfrogs aided discovery about space motion sickness. There's even the possibility that we’ve already exported our first living payload to the Moon: when Israel's Beresheet lunar lander crashed in April of this year, it released thousands of tardigrades – microscopic creatures that we now know can survive unprotected in space.

As we push further into the great beyond, animals are going to be there with us every step of the way. It's a reminder, if ever we needed it, that humanity doesn't exist in a vacuum and our own future is inextricably entwined with the fruit flies, amoebae, cats, dogs and tardigrades that have already forged the way. We can only hope this encourages us all to treat them with more respect down here on the planet we share.