Very Interesting – July-August 2019

47

The real breakthrough could come if we master

the art of synthetic biology – the ability to

design, engineer and build biological structures

from the ground up. Why try and make earthly

plants eke out an existence on Mars when you

can engineer new ones specifically designed to

thrive there? Automated mini-factories known

as biofoundries can test millions of different

designs at once by growing various organisms

in the lab under strictly controlled conditions.

That way, researchers can home in on those

species that are hardy enough to survive. In

July 2018, a team of Australian scientists

published a paper calling for wider investment

in the field, suggesting it could become a

reality in as little as a decade.

COULD WE EAT

OUR OWN POO?

S

cientists at Penn State University

have developed a novel way of

making food, which would save us

having to lug all of our food with us

into space. Yesterday’s human waste

is transformed into tomorrow’s lunch.

Urine is already recycled into

drinkable water on the ISS, but faeces

are sent away in a cargo vessel to

burn up in Earth’s atmosphere.

Dr Lisa Steinberg, who worked at

Penn State before becoming a school

science technician, saw this as a

wasted opportunity, and developed a

system to reuse all of our bodily

outgoings.

“The system is composed of two

reactors,” she says. “The first takes

urine and faeces and converts part of

the carbon [in the waste] into

methane, which is fed to a second

reactor growing a methane-consuming

bacterial biomass.” The result is a

high-protein, high-fat food

supplement. Steinberg points out that

the food can be grown within a few

days – much quicker than plant-based

protein sources such as soybeans.

However, she cautions that it

“would likely complement, not

replace, vegetable matter in an

astronaut’s diet.”

Is it safe? “[The reactors] only transfer

gaseous products, which can be

easily filtered to remove pathogens,”

she says. “Safety was an important

priority.” As for the taste, Steinberg’s

team weren’t able to sample the food

due to lab protocol, but the texture

has been described as similar to

Marmite. Whether astronauts can be

convinced to eat it is another matter.

One of the

International

Space Station’s

two toilets.

“IN 2015, ASTRONAUTS

SAMPLED THE FIRST

LETTUCE GROWN

IN SPACE.”

LEFT: NASA’s Advanced Plant Habitat is a recent

addition to the Space Station.

ABOVE: Kale grown in ‘Martian’ soil, which

actually came from volcanoes here on Earth.

ABOVE RIGHT: NASA’s Steve Swanson tends

to the Vegetable Production System on board

the ISS.

NASA X2, GETTY, EMMA LEE/WHYY

48/2019 33