Mini Hearts and Brains Head to Space Station in First-Ever
Mini Hearts and Brains Head to Space Station in First-Ever Test That Could Unlock Secrets of Faster Aging

CAPE CANAVERAL, Fla. — Miniature human organs are on their way to the International Space Station for the first time, in an experiment researchers hope will reveal how spaceflight affects the body and why living in space appears to speed up aging.

The tiny lab-grown hearts and brains launched Tuesday morning aboard SpaceX's CRS-35 commercial resupply mission from Cape Canaveral Space Force Station in Florida. They are expected to arrive at the space station Thursday.

The project is a joint effort by researchers at the Icahn School of Medicine at Mount Sinai in New York, NASA and aerospace company Space Tango.

Studying space's toll on the body

Astronauts age faster in space because microgravity and increased radiation exposure harm multiple systems in the body, particularly on long-duration missions.

"If people are going to be living and working in space, then we need to understand what's going to happen to them," David Sachs, an assistant professor of surgery at Mount Sinai, told ABC News. "But also, because it's interesting as a model of accelerated aging for studying people on Earth."

Kevin Costa, an associate professor of surgery at Mount Sinai, said the effects can be dramatic.

"Six months in space ... is equivalent to about 10 to 20 years of aging on Earth," Costa told ABC News.

That accelerated timeline gives researchers a unique opportunity to study aging and disease over a much shorter period than would be possible on Earth.

Tiny hearts in orbit

Sachs and Costa are sending up to 16 miniature hearts to the space station. Researchers will test how the tissues respond to electrical signals and monitor how they react to near-zero gravity.

The work builds on an earlier experiment. In 2023, Mount Sinai's Cardiovascular Research Institute sent individual heart cells to the space station, confirming that they could survive in the weightless environment.

Peppercorn-sized brains

The mission is also carrying miniature brain models known as miBrains. About the size of a peppercorn, the miBrains represent both healthy and diseased brains.

By exposing them to the space environment, scientists hope to see how the tiny brains respond and better understand why life in space accelerates aging.

The research could also help scientists studying neurological diseases on Earth.

"[The research is] translating to stuff in space, but it's also translating back to the research we do in the laboratory to help people with Parkinson's and Alzheimer's disease," said Joel Blanchard, an associate professor of stem cell biology, regenerative medicine and neuroscience at Mount Sinai.

A lab the size of a shoebox

The mini organs are housed in a miniature laboratory called a CubeLab, developed by Space Tango, which simulates the natural environment of the human body.

"[It is] slightly bigger than a shoebox, and it is a fully automated, miniaturized system," said Gentry Barnett, Space Tango's chief technology officer.

Researchers say the miniature organs, while not full-sized human organs, are effective substitutes that are cost-effective and take up little of the limited space aboard the station.

Lessons for patients on Earth

Scientists believe findings from the experiments could translate into everyday medical care.

Sachs said the microgravity environment allows researchers to study what happens to people who lead sedentary lifestyles or face prolonged bed rest, conditions that are difficult to simulate on Earth.

Preparing for the moon and Mars

NASA officials said the experiments are a starting point for future research beyond low Earth orbit.

Lisa Carnell, director of NASA's biological and physical sciences division, said scientific tools have advanced dramatically since the Apollo era.

"We sent Apollo astronauts out there over 50 years ago, but the techniques and the way that we can actually do assessments to understand what's happening has come a long way since then," Carnell said.

"We're making leaps, not incremental research, by taking biology to space, because you're seeing changes that you cannot see on the ground in ways you've never seen it before," she added.

NASA plans to return astronauts to the moon's surface in 2028 and build a permanent base there within the next decade. The agency and SpaceX have also discussed sending humans to Mars in the coming years.

Understanding how the body responds to long periods in space will be critical to keeping astronauts healthy on those missions, which could last months or years.

A busy resupply mission

The mini organs are part of a larger cargo shipment aboard SpaceX's Dragon spacecraft. The CRS-35 mission is carrying more than 6,300 pounds of science experiments, crew supplies and equipment, including the final set of new solar arrays to complete an upgrade of the station's power system.

The predawn launch Tuesday produced a striking "space jellyfish" effect, as sunlight illuminated the rocket's exhaust plume high in the atmosphere, visible across parts of the southeastern United States.

What's next

Once the Dragon spacecraft docks with the station, astronauts will transfer the experiments aboard, where the automated CubeLab systems will begin monitoring the mini organs.

Researchers will analyze data collected during the mission and compare the space-exposed tissues with samples kept on Earth, in hopes of uncovering new insights into aging, heart disease and neurological disorders.