KEY POINTS

  • Researchers sent a NASA balloon to Earth's stratosphere
  • The microbes were exposed to Mars-like conditions
  • Scientists found that the black mold fungus spores survived for hours in such conditions

A team of scientists exposed earthly microbes to Mars-like conditions and some of them actually survived, albeit for just a while. The findings come just days after NASA's Perseverance rover landed on the surface of Mars.

Scientists sent a NASA scientific balloon to the sky from Fort Sumner in New Mexico on Sept. 19, 2019. This particular balloon was quite special because it was carrying a MARSBOx with millions of microbes kept at a pressure and atmospheric condition that replicate that of Mars.

The idea is to expose the microbes to Mars-like conditions. This is something that cannot be easily achieved from the surface of Earth, but can be replicated in the stratosphere, the Frontiers blog explained.

This way, the scientists from NASA and German Aerospace Center were able to test the microbes' endurance to Martian conditions without having to go to the Red Planet. In their study, published in Frontiers in Microbiology on Monday, the researchers shared the results of their rather unique experiment.

Microbes in space

For the experiment, the scientists used samples of four different microbes, including fungal and bacterial spores. They placed two sets of samples in a box, with the bottom layer being protected from UV radiation from the sun. In the stratosphere, the samples were exposed to harsh conditions for over five hours.

Once the balloon returned to Earth, the researchers studied the samples and they found that two of the four species actually survived the trip, NASA said. The Aspergillus niger fungus spores were most resistant to the extreme conditions they were exposed to.

"While not all the microbes survived the trip, one previously detected on the International Space Station, the black mold Aspergillus niger, could be revived after it returned home," the study's joint first author, Katharina Siems of the German Aerospace Center, said, according to Frontiers.

One of the possible explanations for how the fungal spores were able to survive is that their pigmentation may be acting rather like a sunscreen that protects their insides.

The scientists said the results of the experiment suggested that the microbe could survive Mars conditions, even just for a few hours.

"If a microbe can hack it up there, above much of the protective ozone layer, it just might be able to survive – however briefly – on a journey to the surface of Mars," study co-author David J. Smith of NASA's Ames Research Center said, according to NASA.

Future Mars missions

Apart from understanding how the microbes can really be in extreme conditions, the experiment also has implications for future Mars missions. This is because there is a risk of carrying contaminants from Earth to the Red Planet during such missions. The study shows that some microbes can, indeed, survive the alien environment, even for just a few hours.

"With crewed long-term missions to Mars, we need to know how human-associated microorganisms would survive on the Red Planet, as some may pose a health risk to astronauts," Siems said in the Frontiers blog. "In addition, some microbes could be invaluable for space exploration. They could help us produce food and material supplies independently from Earth, which will be crucial when far away from home."

Mars seen from the Hubble space telescope
Mars seen from the Hubble space telescope NASA / NASA