Why NASA sent ‘organ chips’ of the Artemis II crew into space

Dr. Catherine Hansen, the wife of Canadian astronaut Jeremy Hansen, says the Artemis II crew told her she could relax 'after splashdown.'

Before four Artemis II astronauts strapped into their Orion capsule to soar toward the moon, a tiny bit of each of them was already on board.

Incubated in a small triangular container stowed on the spacecraft just before launch were four USB-size “avatars,” which rode along with the history-making moon mission. But in many ways, their journey is just beginning.

Known as organ chips, the avatar crewmates are made with bone marrow tissue derived from cells donated by their full-size counterparts — NASA’s Reid Wiseman, Victor Glover and Christina Koch, and Canadian Space Agency astronaut Jeremy Hansen — and researchers believe the experiment could soon unlock unprecedented insights about the effects of space on human health.

The AVATAR, or A Virtual Astronaut Tissue Analog Response, study essentially allows scientists to simulate what happens to astronauts’ organs in deep space.

It offers a more granular look at where and when changes in the body begin, compared to traditional post-flight medical testing, according to Lisa Carnell, Director of NASA’s Biological and Physical Sciences Division. “We’ve never done this before,” she said.

Because researchers chose to focus on bone marrow for this organ chip experiment, Carnell expects to gather data on the crew’s immune responses to traveling through the deep space and the higher-radiation levels associated with such endeavors. Those insights could lead to individualized treatments that ease the way for the astronauts to embark on longer missions — perhaps deeper into the cosmos.

“When we send these alongside Christina, Victor, Reid, Jeremy, they all may respond different to the deep space radiation environment. Somebody may be radio resistant and will learn something new, and you know, or maybe somebody is more extremely susceptible to radiation,” Carnell said before the mission began. “Well, now we can tailor medical kits that we can make personal lives for them on their journey. They go to Mars, they go to the moon, to live for long duration. We can send the right therapeutics with them to make sure they stay healthy and that they can thrive in those environments.”

The goal, Carnell said, is to one day be able to send up avatars of astronauts selected for deep space and long-duration missions ahead of time, so crews can prepare for potential health concerns before they become an issue far from home.

“In the Apollo days, it was just a few days on the surface. If we’re literally going to have people on the surface for a long period of time, even 30 days or longer, I mean, we don’t have data on that at all, right?” Carnell said. “We like to say, ‘Know before we go.’ It’s that simple. Like, how do we know before we send them to ensure that we bring them back healthy and that they’re as safe as can be? And this is such a simple … eloquent way to do that.”

As AVATAR quietly careens along in a corner of the spacecraft, the Artemis II astronauts are also actively working to collect data that could inform the future of human spaceflight — and that job doesn’t end once they splashdown.

The five hazards of space travel

Space is a stressful place for the human body, said Dr. Steven Platts, chief scientist for human research at NASA’s Johnson Space Center in Houston.

The agency has an acronym for the overarching hazards that humans face in space: RIDGE, which stands for radiation, isolation, distance from Earth, gravity (or the lack thereof) and environment (which can be hostile both inside and outside of the spacecraft), Platts said.

Any time humans venture to space, but especially on the rare occasion that they journey beyond Earth orbit, researchers want to monitor as much as they can about the effects of the harsh environment on the body — even if it’s just for 10 days.

There are a number of ways researchers can understand how spaceflight can impact the Artemis II astronauts’ bodies and minds as they ride onboard the Orion spacecraft – which is about the size of a campervan, compared to the International Space Station, which is the size of a six-bedroom home. The crew is sleeping, eating, exercising and working in the small space together.

“I want to see how the crew respond in that much smaller vehicle,” Platts said. “So I want to see how their team dynamic is, how well are they working together? Are there stresses? And, you know, there’s always going to be stresses with a group of people, but being able to track that scientifically is really important.”

To evaluate their mental health, the astronauts are asked a number of questions about their feelings during different parts of the mission, but there are other ways of monitoring their wellbeing, Platts said.

The team has been wearing watch-like wrist monitors to track their movements and sleep in real-time during the mission, which can be compared with pre- and post-flight evaluations. The data, which will contain insights about cognition, behavior and sleep quality in space, could be used while planning crew support measures for future missions.

The astronauts are also collecting their own saliva before, during and after the mission as a way to track unique biomarkers for their immune systems. Since there is no refrigeration unit aboard Orion, they are blotting their saliva on special paper kept in small booklets.

Saliva samples can be used to measure how radiation and other stressors impact the immune system. Researchers will also analyze the samples to see if dormant viruses that cause chickenpox and shingles reactivated in space — something that has been seen in astronauts on the International Space Station.

Artemis II also marks the first time astronauts beyond Earth orbit will participate in the Spaceflight Standard Measures study, an ongoing research project that has collected data from International Space Station astronauts and other spaceflights since 2018.

The participating crew members began by giving blood, urine and saliva samples to provide snapshots of their nutrition, cardiovascular health and immune system starting six months ahead of launch. They also performed tests to glean insights into their balance, muscles, microbiome, vision and brain health. In space, they’ve been evaluating any motion sickness symptoms. And once they return, the crew will go through more tests to assess their head, eye and body movements.

To measure radiation exposure, Orion contains six radiation sensors and each crewmember keeps a monitor in their pocket. The sensors can provide warnings if radiation levels rise to hazardous, which could occur if the sun releases powerful solar flares during the mission.

Returning to an ‘obstacle course’ on Earth

After the astronauts return to Earth, they’ll go through an “obstacle course,” Platts said, which includes climbing a ladder, lifting items and doing maneuvers that may seem tricky upon experiencing our planet’s gravity again.

The obstacle course is helpful not just for reacclimating them to Earth, but also in preparing for what astronauts might experience upon landing on the moon, where they won’t have help getting out of the lander.

“The inner ear is a tricky thing, and we know that that’s affected by spaceflight, and it can be difficult for the crew to move around for a few days when they come back,” Platts said. “It recovers between three and five days, but for those initial days on the lunar surface, we need to know exactly how they’re going to respond.”

Lakiesha Hawkins, acting deputy associate administrator for NASA’s Exploration Systems Development Mission Directorate, noted that the kind of human health data being captured during the Artemis II mission wasn’t collected during the Apollo program.

“The experiments about human health are going to give us data that we need to be able to live on the moon, longer as we develop the moonbase and be able to prepare for trips like going on to Mars,” Hawkins said.