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Pioneer Labs' 'first microbe for Mars' makes bioplastic in a tank, researchers say
Erika DeBenedictis of Pioneer Labs told more than two million X viewers her engineered Cupriavidus necator was "the first microbe for Mars." Researchers who reviewed the preprints, including NASA's Chris McKay, say it only grows in a sealed bioreactor and cannot alone revive a dead planet.
The Scientist · Science desk
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What happened
- Chris McKay, a NASA Ames planetary scientist and the harshest of the reviewers, said the engineered bacterium is 'not very interesting, not very new yet.'
- The other researchers Scientific American consulted across planetary science, astrobiology, microbial ecology and bioengineering were, on the whole, positive.
- Mars has an atmosphere about 1 percent as thick as Earth's, surface radiation, and temperatures that can swing 100 degrees Celsius in a single Martian day.
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Why it matters
- contradiction Pioneer Labs frames sPL.001 as 'the first step towards terraforming,' while McKay says its real job is feedstock for 3D-printed houses, so the two sides disagree on what a tank-bound microbe should be called.
- constraint Because sPL.001 works only inside a bioreactor fed Martian dirt, water and compressed carbon dioxide by machinery, it is an industrial input, not an organism that could spread across open ground.
- precedent By DeBenedictis's own count, four more organisms are still needed, at least one green and able to grow on Mars, so a living Mars is several undemonstrated microbes away.
What sPL.001 actually does, by Pioneer Labs' own account, is consume Martian dirt, water and compressed carbon dioxide fed into a bioreactor by autonomous machinery, then pump out a form of bioplastic. [3][12] That bioplastic is a building material. Chris McKay, a planetary scientist at NASA's Ames Research Center who has studied terraforming for decades, said sPL.001 is for making feedstock for 3D-printed houses, not for terraforming Mars. [10][5] "It can only be grown in a bioreactor," he added. [11]
McKay is not hostile to the larger idea. He is senior author of "The Case for Mars Terraforming Research," a paper led by DeBenedictis and published last year in Nature Astronomy. [6] His objection is about novelty. The engineered bacterium, he said, is "not very interesting, not very new yet." [7] The announcement came with several recent preprints on the company's work. [21] Paul Race, who studies industrial biotechnology at Newcastle University, called it "rather over the top," though most of the other researchers Scientific American consulted were, on the whole, positive. [9][4]
DeBenedictis has been plain about the limits. On Pioneer Labs' Substack she wrote that sPL.001 "is the first of five organisms we will need to make Mars green." [13] That leaves four still to engineer, and none has been shown to exist. [1] McKay replied that he hoped some of the other four would be green and could actually grow on Mars. [14]
Growing in the open is the hard part. Mars has an atmosphere about 1 percent as thick as Earth's, bathes its surface in harmful radiation, and can swing 100 degrees Celsius in a single Martian day. [17] Nitrogen, which life needs, is scarce in both the air and the soil. [18] sPL.001 sidesteps all of it by living in a sealed tank. [11]
The company's name comes from "pioneer species," the molds, lichens and dandelions that colonize bare rock and build the soil that later plants need. [16] DeBenedictis, a synthetic biologist with a doctorate from MIT, founded Pioneer Labs in 2024 as a resident at the billionaire-backed Astera Institute in the San Francisco Bay Area. [15][19] Those pioneer species, she told Scientific American, let "fancier organisms and shrubs and trees and stuff to grow, and that's exactly what we're trying to do" for Mars. [20]
What to watch
- Whether Pioneer Labs engineers and demonstrates any of the other four organisms, especially one that is green and can grow outside a bioreactor.
- Whether the preprints behind the announcement hold up in peer review.
- Whether sPL.001 is tested on real Martian regolith conditions rather than only in a lab bioreactor.