Can AI robots replace human astronauts?

On Christmas Eve, an autonomous spacecraft flew closer to the Sun than any man-made object before it. After flying through the atmosphere, NASA’s Parker Solar Probe was on a mission to learn more about the Sun, including how it affects space weather on Earth.

It was a landmark moment for humanity, but without direct human involvement, as the spacecraft performed its pre-programmed tasks on its own as it flew past the sun without communicating with Earth.

For the past six decades, robotic probes have been sent around the solar system, reaching places impossible for humans. During his 10-day flybyThe Parker Solar Probe experienced a temperature of 1000C.

But the success of these autonomous spacecraft — combined with the rise of new, advanced artificial intelligence — raises the question of what role humans might play in future space exploration.

Some scientists question whether human astronauts will be needed at all.

“Robots are developing rapidly and the case for sending humans is weakening all the time,” says Lord Martin Rees, Britain’s Astronomer Royal. “I don’t think taxpayer money should be used to send people into space.”

It also indicates the risk to humans.

“The only case for sending people (there) is an adventure, an experience for wealthy people, and it should be privately funded,” he argues.

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

They are also cheaper than humans, he claims. “And as artificial intelligence advances, robots are getting smarter and smarter.”

But what does this mean for future generations of aspiring astronauts – and of course there are certain functions that humans can perform in space, but which robots, however advanced, never could?

Robotic spacecraft have visited all the planets in the solar system, as well as many asteroids and comets, but humans have visited only two destinations: Earth orbit and the Moon.

A total of about 700 people have been in space since 1961, when Yuri Gagarin of the then Soviet Union became the first space explorer. Most of them were in orbit (around the Earth) or in sub-orbit (short vertical jumps into space lasting a few minutes on such vehicles as the New Shepard rocket of the American company Blue Origin).

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

But apart from an innate desire to explore or a sense of prestige, people also conduct research and experiments in Earth orbit, such as the International Space Station, and use them to advance science.

Robots can contribute to these scientific studies by being able to travel to places inhospitable to humans, where they can use instruments to study and explore the atmosphere and surface.

“Humans are more diverse and we can do our tasks faster than robots, but it is very difficult and expensive for us to maintain life in space,” says Dr. Weinersmith.

In her novel Orbital, which won the 2024 Booker Prize, writer Samantha Harvey waxes more lyrical: “A robot needs no hydration, no nutrients, no excretion, no sleep… It wants and asks for nothing.”

But there are also disadvantages. Many robots are slow and methodical – on Mars, for example, rovers (remotely controlled vehicles) move at a speed of only 0.1 miles per hour.

“Artificial intelligence can beat humans at chess, but does that mean they can beat humans at environmental studies?” – asks Dr. Ian Crawford, a planetary scientist from the University of London. “I just don’t think we know.”

However, he believes that artificial intelligence algorithms can make rovers more efficient.

Technology can play a role in supplementing human space travel by freeing astronauts from certain tasks and allowing them to focus on more important research.

“(AI can be used to) automate tedious tasks,” explains Dr. Kyrie Wagstaff, a US computer and planetary scientist who previously worked at NASA’s Jet Propulsion Laboratory in California. “On the surface of the planet, people get tired and lose focus, but machines don’t.”

The problem is that systems like large-scale language models (LLMs), which can understand and generate human language by processing huge amounts of textual data, require enormous amounts of power to run. “We are not yet in a position to do an LLM on the rover,” says Dr Wagstaff.

“The rover’s processors run about one-tenth (of the speed) of your smartphone” — meaning they can’t handle the high demands of running the LLM.

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

NASA’s Valkyrie robot was created by the Johnson Space Center to participate in a robotics test in 2013. Weighing in at 300 pounds and standing 6’2″, it looks nothing like a Star Wars stormtrooper, but it’s one of a growing number of humanoid machines with superhuman abilities.

Long before Valkyrie was created by NASA Rabonaut was the first humanoid robot designed for use in space, taking over tasks otherwise performed by humans.

His specially designed hands meant he could use the same tools as astronauts and perform complex, delicate tasks, such as grasping objects or flicking switches, that were too difficult for other robotic systems.

A later model Robonaut was delivered to the International Space Station on 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 with a robot,” says Dr. Shawn Azimi, head of the agile robotics team at NASA’s Johnson Space Center in Texas. “We see robots as a way to protect these habitats when people aren’t around.”

He argues that robots may be useful not to replace human researchers, but to work alongside them.

Some robots already operate on other planets without humans, sometimes even making decisions on their own. For example, NASA’s Curiosity rover exploring region called Gale Crater on Mars and is autonomously performing some of its science without human involvement.

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

“He can get the readings of a certain stone and send it back to Earth while people 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. That is, humans have the added bonus of inspiring people to Earth in a way that machines cannot.

“Inspiration is something intangible,” says Professor Coates.

Leroy Chiao, a retired NASA astronaut who flew three space flights in the 1990s and 2000s on NASA’s space shuttle and to the International Space Station, agrees. “People communicate when people do something.

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

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

The the next mission with the crew in 2026 four astronauts will fly around the moon. Another mission, planned for 2027, will allow NASA astronauts to land on the surface of the Moon.

The Chinese space agency, meanwhile, also wants to send astronauts to the moon.

In another, Elon Musk, the CEO of the American company SpaceX, has his own plans related to space. He said his long-term plan is to create a colony on Mars where humans could live land.

His idea is to use the Starship, a huge new vehicle his company is developing, to carry up to 100 people at a time, with the goal of a million people on Mars in 20 years.

“Musk argues that we need to move to Mars because it can be a backup for humanity if something catastrophic happens on Earth,” Dr. Weinersmith explains. “If you accept that argument, then sending people into space is necessary.”

However, there are many unknowns about life on Mars, including many technical challenges that she says remain unresolved.

“Maybe kids can’t thrive in that kind of environment,” she says. “There are ethical questions for which we do not have answers.

“I think we should slow down.”

However, Lord Rhys has his own vision in which human and robotic research can merge to the point where humans themselves become part of the machines to cope with extreme conditions. “I can imagine they’ll use all sorts of genetic modification techniques, cyborg additions and so on to deal with a very hostile environment,” he says.

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

Until then, however, humans will likely continue their baby steps into space along a path long trodden by robotic explorers before them.

Main image credit: NASA

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