NASA scientists grew chile peppers on the International Space Station to see if astronauts could have fresh food in space. They successfully harvested over 25 peppers and tested them for harmful bacteria and germs. The good news: the peppers were safe to eat with very few germs on them, and no dangerous food-poisoning bacteria were found. The study also discovered which types of bacteria naturally live on the peppers. This research shows that growing fresh vegetables in space is possible and could help astronauts stay healthier on long space missions by giving them fresh food instead of just pre-packaged meals.

The Quick Take

  • What they studied: Whether chile peppers grown in a special plant-growing room on the International Space Station would be safe for astronauts to eat
  • Who participated: 25+ chile pepper plants grown in the Advanced Plant Habitat (APH) on the ISS, with samples tested for bacteria and germs
  • Key finding: The peppers were very clean and safe—they had almost no harmful bacteria on them, and no dangerous food-poisoning germs were detected at all
  • What it means for you: This suggests that growing fresh vegetables in space is possible and safe, which could eventually mean astronauts on long missions could eat fresh food instead of only pre-packaged meals. However, this is just one successful test, so more research is needed before this becomes routine.

The Research Details

NASA scientists used a special enclosed plant-growing room called the Advanced Plant Habitat (APH) on the International Space Station to grow chile pepper plants. They carefully controlled the temperature, light, water, and air inside this room to create the best conditions for the peppers to grow. The peppers were grown for about 4-5 months until they were fully mature and ready to harvest.

Once the peppers were picked, half were eaten by the astronauts on the station, and half were frozen at extremely cold temperatures (-80°C, which is about -112°F) and brought back to Earth in a special container. Scientists then tested these frozen peppers in laboratories to count how many bacteria and fungi (like mold) were living on them. They also used special DNA testing to identify exactly which types of bacteria were present.

Understanding whether plants grown in space stay clean and safe is crucial for NASA’s long-term plans to send astronauts on missions to the Moon and Mars. These missions could last months or years, and astronauts need fresh, nutritious food to stay healthy. This study shows that the special growing room works well and keeps plants safe, which is an important first step toward making space farming a real part of future missions.

This was a real-world test on the actual International Space Station, which makes it very valuable. The researchers used proper scientific methods to count and identify bacteria. However, this was a single demonstration with one type of pepper, so the results are a good starting point but not definitive proof that all space-grown vegetables will always be safe. The study was published in a respected scientific journal (Scientific Reports), which means other scientists reviewed it before publication.

What the Results Show

The chile peppers grown on the ISS were remarkably clean. When scientists tested them for bacteria and fungi, they found very low numbers—ranging from basically none up to a maximum of 111 bacteria per gram of pepper (for reference, a pepper weighs about 100-200 grams). Most importantly, none of the dangerous bacteria that cause food poisoning in humans were found on any of the peppers.

The scientists also identified the types of bacteria that were naturally present on the peppers. They found about 13 different types of bacteria that appeared to be a normal part of the pepper’s natural community. Some of these bacteria had been found before in water samples from the ISS, suggesting they may have come from the space station’s environment.

The study showed that different parts of the growing room and different parts of the pepper plants had slightly different communities of bacteria, which suggests that bacteria may have moved around within the growing system. However, this movement didn’t result in any harmful contamination.

The research revealed that the Advanced Plant Habitat successfully maintained the right conditions for peppers to grow all the way to maturity in space—something that hadn’t been proven before with a long-duration fruiting crop. The peppers grew for 109-137 days and produced a good harvest of both red and green peppers. The study also confirmed that the special growing room’s environmental controls worked as designed, which is important for future space farming projects.

This is one of the first studies to grow a fruiting crop (a plant that produces food) all the way to harvest on the ISS and test it for safety. Previous research had grown lettuce and other leafy greens in space, but peppers are more complex because they take longer to grow and produce seeds inside the fruit. This study builds on that earlier work and shows that the technology can handle more challenging crops. The low bacterial counts found on these space-grown peppers are similar to or better than what’s typically found on vegetables grown in controlled environments on Earth.

This study only tested one type of pepper variety, so we don’t know if other pepper varieties or other types of vegetables would have the same results. The sample size was relatively small (25+ peppers), so larger studies would help confirm these findings. The study was also a one-time demonstration, so we don’t know if the same safe results would happen every time peppers are grown in space. Additionally, the peppers were frozen immediately after harvest, which might have affected the bacteria counts compared to fresh peppers. Finally, the study didn’t test how the peppers would be handled and stored during the long journey back to Earth, which could affect food safety in real missions.

The Bottom Line

Based on this research, growing fresh peppers on the ISS appears to be safe and feasible (confidence level: moderate). The peppers were clean and free from dangerous bacteria. However, more studies with different vegetables and multiple growing cycles are needed before this becomes a standard practice. For now, this research supports continued development of space farming technology. Astronauts and mission planners should view this as promising evidence that fresh food in space is possible, but not yet as a guaranteed solution.

This research is most relevant to NASA and other space agencies planning long-duration missions. It’s also interesting to scientists studying how to grow food in extreme environments and to people interested in space exploration. While the general public won’t immediately see changes, this research could eventually lead to better nutrition for astronauts and might inspire new farming technologies used on Earth. People interested in sustainable food production or extreme-environment agriculture may also find this relevant.

This was a one-time demonstration, so there’s no ongoing timeline for benefits. However, if NASA continues this research and conducts more growing cycles, we might see space-grown vegetables become a regular part of astronaut diets within the next 5-10 years for missions to the Moon or Mars. On Earth, the technology and lessons learned could potentially be adapted for use in extreme environments or areas with limited growing space within a similar timeframe.

Want to Apply This Research?

  • Users interested in space exploration or sustainable food could track ‘space agriculture milestones’ by logging when new crops are successfully grown in space, noting the type of crop, harvest date, and safety results. This creates a personal record of humanity’s progress toward space farming.
  • Users could commit to learning more about space agriculture by reading one article per month about NASA’s plant-growing experiments, or they could support this research by following space agencies’ updates on their food production programs.
  • Set up notifications for new research publications about space farming and ISS plant experiments. Users could maintain a ‘space food timeline’ in the app, tracking which crops have been successfully grown in space and their safety profiles, creating a living database of space agriculture achievements.

This research describes a single successful demonstration of growing peppers on the International Space Station. While the results are promising, this study does not establish that all space-grown vegetables are safe for consumption, nor does it replace standard food safety protocols. The findings are preliminary and based on one crop variety under specific conditions. Anyone involved in space agriculture or food safety decisions should consult with food safety experts and conduct additional research before implementing space-grown produce in operational settings. This information is for educational purposes and should not be considered medical or food safety advice.