NASA astronauts aboard the ISS have begun growing chile peppers in a bid to boost crews' diets on future missions

• NASA astronauts have begun growing chile peppers in space aboard the ISS.
• Crew members will be able to enjoy the spicy snacks in about four months, the agency said.
• Peppers are highly nutritious, making them a great choice for crews during deep-space exploration.

NASA astronauts are spicing things up in space.

In recent days, astronauts aboard the International Space Station (ISS) started growing chile peppers as part of the agency's food crop production experiments.

The pepper seeds arrived at the space station aboard SpaceX's 22nd commercial resupply services mission, which launched back in June.

The Plant Habitat-04 experiment (PH-04), which will cultivate 48 Hatch chile pepper seeds, will grow for about four months before astronauts harvest them. Astronauts will be able to enjoy the peppers when they turn red signaling their ripeness - but they can also be eaten green, the agency said.

Shane Kimbrough, a flight engineer who is part of NASA's SpaceX Crew-2 mission, kicked off the experiment by watering the seeds. This is not the first time Kimbrough has grown crops in space, according to NASA. Back in 2016, he helped grow and eat "Outredgeous" red romaine lettuce as part of the Veg-03 experiment.

The peppers will be grown in the Advanced Plant Habitat (APH), a plant growth cell approximately the size of a kitchen oven, according to the agency. It is one of three plant growth chambers on the orbiting laboratory where astronauts cultivate crops.

"The APH is the largest plant growth facility on the space station and has 180 sensors and controls for monitoring plant growth and the environment," said Nicole Dufour, PH-04's project manager. "It is a diverse growth chamber, and it allows us to help control the experiment from Kennedy, reducing the time astronauts spend tending to the crops," she added.

It is the first time NASA astronauts will grow a crop of chile peppers on the station from seeds to maturity. Matt Romeyn, chief investigator for PH-04, said: "It is one of the most complex plant experiments on the station to date because of the long germination and growing times."

Why peppers?

They are rich in vitamin C and several other key nutrients, said Romeyn. Peppers are also sturdy with a good chance of growing successfully in microgravity. They are also easy to handle as a pick-and-eat crop that does not require cooking.

Its colour also makes it well suited for astronauts aboard the space station. "Growing colorful vegetables in space can have long-term benefits for physical and psychological health," Romeyn said. "We are discovering that growing plants and vegetables with colors and smells helps to improve astronauts' wellbeing."

Taste is a crucial element of the experiment. LaShelle Spencer, PH-04's project science team leader, said: "The spiciness of a pepper is determined by environmental growing conditions. The combination of microgravity, light quality, temperature, and rootzone moisture will all affect flavor, so it will be interesting to find out how the fruit will grow, ripen, and taste."

This is because the food astronauts eat not only needs to be the most nutritious but also the tastiest. Crew members in space can lose their sense of taste and smell as a short-term effect of living in microgravity, and so they may prefer spicy foods or foods rich in flavour, said Romeyn.

There is a lot of work being done in space agriculture from a nutritional and supplemental perspective, where astronauts are growing a full menu in zero-gravity. In May, astronauts aboard the ISS enjoyed a fresh supply of vegetables, including "Amara" mustard, also known as Ethiopian kale, and the previously grown crop, "extra dwarf" pak choi.

The experiments come in an effort to help find solutions to feed crews on future long-duration missions to the moon and eventually Mars, said NASA.