The International Space Station is the cleanest, most carefully engineered spacecraft humans have ever built, yet run a swab across a single handrail, and you are very much not alone. Every crew member, meal, and cargo delivery carries trillions of tiny stowaways: bacteria and fungi that live in the air, water, and on the surfaces of the station.
On this episode of Teen Scientist, host Aryash Shyam talks with Dr. Sarah Wallace, a microbiologist at NASA’s Johnson Space Center whose team made it possible to sequence DNA in space for the first time, about the invisible ecosystem that travels with astronauts, and why NASA works so hard to keep track of it.
Dr. Wallace explains how NASA moved from “grow and return” (flying samples all the way back to Earth just to ask what they are) to “sequence in orbit,” using a candy-bar-sized device called the MinION that reads DNA by threading it through tiny pores. She and Aryash explore why most microbes are not villains, how knowing what is growing on a spacecraft protects both the crew and its water system, and why identifying microbes on board becomes essential on long missions to the Moon and Mars. It gets personal, too: Aryash, a Genes in Space Junior Scientist Award winner, asks what advice she would give students designing biology experiments they hope could one day fly in space.
Teen Scientist with host Aryash Shyam brings you groundbreaking innovation in science, technology, engineering, and mathematics disciplines, entirely from a teenage perspective. Catch it the first Thursday of every month from 6:00 to 6:30 PM following All Things Considered.
(Original air-date: 11/5/26)
