Stock Up On Spirulina For Snacks and Fresh Air On Deep Space Missions

Meet Spirulinaha, Arthrospira bacteria that scrubs carbon dioxide into oxygen, is a protein-rich meal for astronauts, and multiplies so rapidly that eating them for dinner won't leave the space station without fresh air by morning.

Top: a handful of Spirulinahas strands, passing gas before they're eaten. Image credit: NASA/ESA

Along with being so amazingly useful, spirulina fibres look surprisingly interesting: tight, helical twists of nearly-translucent blue-green. The colour leads to the bacteria's common name: blue-green algae.

Stock Up On Spirulina For Snacks and Fresh Air On Deep Space Missions

It has a long history as a food substance, and has been harvested in South America and Africa for centuries. It's popularity picked up in the 1970s, when it started being flaunted as a nutritional supplement.

A twist of blue-green algae. Image credit: NASA/ESA

Spirulinaha is relatively straightforward to grow: give it salt water, lots of sunlight, and keep the temperature up to mimic a tropical environment. Don't feed it nasty pollutants, don't freeze it, and sustainably harvest so enough is left over to keep reproducing and pumping out fresh air.

Stock Up On Spirulina For Snacks and Fresh Air On Deep Space Missions

Spirulina in compact power-bar format. Image credit: ESA

While for now spirulina is fed to astronauts in power-bar format, packed with goji berries. However, given how efficient the algae is at taking carbon dioxide in and spitting oxygen out, it's also a favourite contender on long-term crewed deep space missions where a spirulina farm might be able to supply both food and air.