Can artificial intelligence robots replace human astronauts?

On Christmas Eve, an autonomous spacecraft flew by the sun, closer than any man-made object before it. As it swoops through the atmosphere, NASA's Parker Solar Probe is on a mission to discover more about the Sun, including how it affects space weather on Earth.

This was a historic moment for humanity – but without any direct human intervention, as the spacecraft carried out its pre-programmed missions on its own as it flew by the Sun, with no contact with Earth at all.

Robotic probes have been sent across the solar system over the past six decades, reaching destinations impossible for humans. During its flight for 10 daysThe Parker Solar Probe has seen temperatures of up to 1,000 degrees Celsius.

But the success of these autonomous spacecraft – coupled with the emergence of new advanced artificial intelligence – raises the question of what role humans might play in future space exploration.

Some scientists wonder whether human astronauts are needed at all.

“Robots are evolving rapidly, and the case for sending humans is getting weaker all the time,” says Lord Martin Rees, the UK's astronomer royal. “I don't think any taxpayer money should be used to send humans into space.”

It also indicates danger to humans.

“The only case for sending people[there]is an adventure, an experiment for the wealthy, and it has to be privately funded,” he says.

Andrew Coates, a physicist from University College London, agrees with this opinion. “For serious space exploration, I much prefer robots,” he says. “(They) go much further and do more things.”

They're also cheaper than humans, he says. “As artificial intelligence advances, robots can become smarter and smarter.”

But what does this mean for future generations of budding astronauts? Surely there are certain jobs that humans can do in space, but robots, no matter how advanced, can never do them?

Robotic spacecraft have visited every planet in the solar system, as well as many asteroids and comets, but humans have only been to two destinations: Earth orbit and the moon.

In all, about 700 people have been in space since 1961, when Yuri Gagarin of the then-Soviet Union became the first cosmic explorer. Most were in orbit (orbiting the Earth) or suborbit (short vertical jumps into space lasting minutes, on vehicles such as US company Blue Origin's New Shepard rocket).

“Prestige will always be a reason for humans to be in space,” says Dr. Kelly Weinersmith, a biologist at Rice University in Texas and co-author of A City on Mars. “It seems to have been agreed upon as a great way to show that your political system works and your people are great.”

But apart from the innate desire to explore, or a sense of awe, humans also conduct research and experiments in Earth's orbit, such as on the International Space Station, and use them to advance science.

Robots can contribute to this scientific research, with the ability to travel to places inhospitable to humans, where they can use tools to study and probe atmospheres and surfaces.

“Humans are more versatile and get things done faster than a robot, but surviving in space is really difficult and expensive,” says Dr. Weinsmith.

In her 2024 Booker Prize-winning novel Orbital, author Samantha Harvey puts it more lyrically: “A robot has no need of water, nutrients, excretion, sleep… it wants and asks for nothing.”

But there are downsides. Many robots are slow and methodical – for example on Mars, rovers (remotely controlled robotic vehicles) move at barely 0.1 mph.

“AI can beat humans at chess, but does that mean they will be able to beat humans at exploring environments?” asks Dr. Ian Crawford, a planetary scientist at the University of London. “I just don't think we know.”

However, he believes that AI algorithms may enable rovers to be “more efficient.”

Technology could play a role in complementing human space travel by freeing astronauts from certain tasks to allow them to focus on more important research.

“AI can be used to automate tedious tasks,” explains Dr. Kerry Wagstaff, a US computer and planetary scientist who previously worked at NASA's Jet Propulsion Laboratory in California. “On the planet, humans get tired and lose focus, but machines won't.”

The challenge is that huge amounts of power are needed to run systems such as large language models (LLM), which can understand and generate human language by processing huge amounts of textual data. “We're not close to being able to run an LLM on a Mars rover,” says Dr. Wagstaff.

“The rovers' processors run at about a tenth (as fast) as your smartphone” — meaning they're unable to handle the intense demands of running an LLM.

Complex humanoid machines with robotic arms and limbs are another form of technology that can handle basic tasks and functions in space, especially as they more closely mimic the physical capabilities of humans.

NASA's Valkyrie robot was built by the Johnson Space Center to compete in the 2013 Robotics Challenge experiment. Weighing 300 pounds and standing 6 feet 2 inches tall, it's not unlike a Star Wars Stormtrooper, but it's one of a growing number of humanoid machines with superpowers .

Long before Valkyrie was created, NASA was Robonaut It was the first humanoid robot designed for use in space, where it took over tasks previously performed by humans.

Its specially designed hands mean it can use the same tools as astronauts and perform complex and delicate tasks such as grasping objects or clicking keys, which would have been extremely challenging for other robotic systems.

A later model of Robonaut was flown to the International Space Station aboard the Space Shuttle Discovery in 2011, where it assisted with maintenance and assembly.

“If we need to change a component or clean a solar panel, we can do it robotically,” says Dr. Sean Azimi, skilled robotics team leader at NASA's Johnson Space Center in Texas. “We see robots as a way to secure these habitats when humans aren't around.”

He believes that robots could be useful, not to replace human explorers, but to work alongside them.

Some robots are already operating on other planets without humans, sometimes making decisions themselves. For example, NASA's Curiosity spacecraft is exploration An area called Gale Crater on Mars independently performs some of its science without human intervention.

“You can direct the rover to take images of a scene, look for rocks that might fit the science priorities of the mission, and then fire the laser autonomously at that target,” says Dr. Wagstaff.

“It can get a reading of a specific rock and send it back to Earth while humans are still asleep.”

But the capabilities of rovers like Curiosity are limited by their slow pace. And there's something else they can't compete with either. This means that humans have the added benefit of inspiring people to return to Earth in a way that machines cannot achieve.

“Inspiration is something intangible,” says Professor Coates.

Leroy Chiao, a retired NASA astronaut who went on three spaceflights in the 1990s and 2000s aboard NASA's space shuttle and to the International Space Station, agrees. “Humans communicate when humans do something.

“The general public is excited about robotic missions. But I expect the first human on Mars to be bigger than the first moon landing.”

Humans have not traveled further than Earth's orbit since December 1972, when the last Apollo mission visited the Moon. NASA hopes to return humans there this decade through the Artemis program.

the The next manned mission It will see four astronauts journey around the moon in 2026. Another mission, scheduled for 2027, will see NASA astronauts land on the moon's surface.

Meanwhile, the Chinese Space Agency also wants to send astronauts to the moon.

Elsewhere, Elon Musk, CEO of US company SpaceX, has his own space-related plans. He said his long-term plan is to establish a colony on Mars, where humans can land.

His idea is to use Starship, a huge new vehicle his company is developing, to transport up to 100 people there at one time, with the aim of being there. One million people on Mars in 20 years.

“Musk says we need to move to Mars because that could be a backup for humanity if something catastrophic happens on Earth,” explains Dr. Weinersmith. “If this argument holds true, then sending humans into space is essential.”

However, there are big unknowns about living on Mars, including a myriad of technical challenges that she says remain unresolved.

“Children may not be able to thrive in that environment,” she says. “There (are) ethical questions (like this) that we don't have answers to.

“I think we should slow down.”

However, Lord Reese has a vision of his own, where human and robotic exploration might merge to the point where humans themselves are part of a machine to cope with harsh environments. “I can imagine they would use all kinds of genetic modification techniques, cyborg additives, etc., to deal with very hostile environments,” he says.

“We may have a new species that would be happy to live on Mars.”

But until then, humans will likely continue their baby steps into the cosmos, on a path long trodden by robotic explorers before them.

Top image credit: NASA

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