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Why is NASA sending slime mold to the space station?

It’s not just astronauts and billionaires who get to ride on rockets these days. In recent months, everything from squid and water bears to flatworms and mice have also made the journey from Earth to space, though admittedly their missions were at the behest of scientists rather than the result of any expressed desire to experience life off-planet.

The next life form to blast off for a stay on the International Space Station (ISS) will be a naturally occurring slime mold known as Physarum polycephalum.

The naturally occurring mold will head to the ISS aboard Northrop Grumman’s 16th commercial resupply services mission set for launch on August 10.

New experiments headed to the @Space_Station could help us construct habitats on other planets, analyze muscle loss, study slime molds in microgravity, and more!

— ISS Research (@ISS_Research) July 26, 2021

Upon arrival, astronauts will use the substance to launch an investigation called Blob, conducted in partnership with the European Space Agency (ESA) and a group of Earth-based students aged between 10 and 18.

Incredibly, the slime mold is capable of basic forms of learning and adaptation. “Although it is just one cell and lacks a brain, Blob can move, feed, organize itself, and even transmit knowledge to other slime molds,” NASA said.

According to, “specimens of Physarum polycephalum can be found on decaying leaves and tree trunks in cool, moist spots. The slime moves from place to place, albeit very slowly, by extending finger-like protrusions called pseudopods.”

Using samples of the slime mold on Earth, the students will replicate experiments carried out by current ISS crew member Thomas Pesquet to see how microgravity affects the mold’s behavior. Time-lapse video will be used to help students more easily compare the speed, shape, and growth of the slime molds in space and on the ground.

“Blob is a unique experience that stimulates student curiosity about themes such as the impact of the environment on organisms and the development of living organisms,” said Evelyne Cortiade-Marché of France’s National Center for Space Studies that’s also overseeing the study. She added that the educational experiment “offers the opportunity to carry out a real scientific experimental process in a playful, collaborative, and media-oriented context.”

If only the slime mold sample knew what joy it’s about to bring those students back on terra firma. Maybe it does.

Other items destined for the ISS on next month’s Cygnus resupply mission include material simulating lunar and Martian soil that will be used to test 3D printing in space with a view to building structures on other planets for future crewed missions, and the latest technology designed to efficiently remove carbon dioxide from a spacecraft.

Trevor Mogg
Contributing Editor
Not so many moons ago, Trevor moved from one tea-loving island nation that drives on the left (Britain) to another (Japan)…
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