How yeast will teach NASA about the dangers of space

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A NASA spacecraft passing by the moon on Monday is carrying 12,000 varieties of yeast. Researchers hope the tiny "yeastronauts" can teach them about how radiation will affect humans in space.

Transcript

STEVE INSKEEP, HOST:

This morning, a NASA spacecraft is passing by the moon on its way back to Earth. There are no astronauts on the capsule, but there is life on board. NPR's Geoff Brumfiel reports on microscopic space travelers.

GEOFF BRUMFIEL, BYLINE: Space is dangerous, and one of the most dangerous things about it is radiation.

LUIS ZEA: We need to understand what this radiation can do to us and what are the mitigation approaches that we need to take.

BRUMFIEL: Luis Zea is principal investigator of an experiment now passing by the moon aboard NASA's Orion capsule. It's designed to test how life holds up under assault from all kinds of radiation, from solar wind to cosmic rays. But his spacefarers are maybe not what you'd expect.

ZEA: We're flying about 12,000 mutants of yeast.

BRUMFIEL: That's right - yeast, like what we use to make bread and beer back here on Earth. Zea and his team stashed them under a seat. When I visited him at the University of Colorado, Boulder in November, he and his colleague Tobias Niederwieser showed me a copy of the experiment. They took me into a lab, and there it was, about the size of a lunchbox.

TOBIAS NIEDERWIESER: Here are four bags that are filled with yeast capsule. So it's these little pellets that you can see right here. They're lyophilized, so they're freeze-dried.

BRUMFIEL: After Orion started its journey to the moon last month, the bags filled with nutrients, and the yeast began growing. The experiment is running automatically.

NIEDERWIESER: It is doing everything itself.

BRUMFIEL: Now, it might surprise you that NASA would let yeast of all things aboard its multibillion-dollar spaceship, the one it hopes will someday land the first woman and first person of color on the moon. But Zea says yeast can teach us a lot about how human astronauts can withstand radiation.

ZEA: We don't look alike at all, but we have a lot of overlap between their genome and ours. And you can fly trillions of them in a tiny little bag, which you cannot do with humans, right?

BRUMFIEL: Zea's team genetically modified each group of yeast to have a single tweak to its genome. He expects some mutants will survive better than others. And when the experiment gets back to Earth...

ZEA: We're going to be able to pull out the DNA and then do the counts of how many of each of the mutants survived.

BRUMFIEL: Ultimately, Zea says, these yeasty beasties may lead to drugs that can enhance the human body's own ability to protect against radiation, and that could help astronauts traveling into the final frontier.

Geoff Brumfiel, NPR News. Transcript provided by NPR, Copyright NPR.