A recent research study has discovered that the moon is no longer an inhabitable place, but for Earth microbes.
NASA-led research has indicated that certain five kinds of fungi and bacteria can survive for weeks to months in specific lunar regions under serious conditions, thereby raising the concerns regarding unintended life transfer to the moon.
These microbes were tested in a simulation of three regions near the lunar South Pole. In the experimental phase, environmental conditions based on observations by NASA’s Lunar Reconnaissance Orbiter and data on radiation exposure were used.
As per findings, fungi proved harder than bacteria. Among all fungal species, Aspergillus niger, also called black mold, was found to be more resilient. Besides surviving in warmer climates, these species also found it inside the International Space Station.
Experiments showed it can even survive outside the station while in orbit. “Aspergillus was the most well-suited to survive in regions of the lunar poles. Fusarium was similarly resilient, though not to the extent of Aspergillus,” said Saxena, lead author of the study published in the journal Science Advances.
Speaking about bacteria species, three species including Deinococcus radiodurans, Staphylococcus aureus, and Bacillus subtilis were found to be less resilient to UV radiation and heat.
“The bacteria we examined were less resilient to ultraviolet radiation and consequently had less survival, with Deinococcus leading the way and Staphylococcus and Bacillus bringing up the rear,” Saxena said.
Goddard Space Flight Center organic geochemist and study co-author Heather Graham, said “Our study focused only on the survival of these cells, not their growth or reproduction.”
“But there are scenarios where cells can get buried, which would keep them warm and protected from radiation. There may also be scenarios where pockets of liquid water could form, which would potentially help the organisms grow,” Graham added.
Impact on future lunar missions
When it comes to the space race, both countries, China and the US, are racing to mark their dominance on the lunar surface. Nasa’s Artemis missions are meant to land astronauts around the South Pole region. China is also planning to land astronauts on the moon by 2030.
There is growing concern that survival of Earth microbes and the contamination they brought can distort scientific understanding of the moon.
“We found that the lunar South Pole and North Pole possess significant regions that may allow common human-associated microbes to survive long enough to impact scientific operations and exploration,” Saxena said.
So, unintended life transfer via spacesuits, tools, or machinery could contaminate future sample analyses and complicate the search for native lunar chemistry, making strict tracking essential for future Artemis missions.
“Hardiness of these organisms means they can affect future sample analyses to help us understand things like chemical makeup of the regolith (lunar surface material) or the presence of certain organic molecules. Contamination is unavoidable, so we need to track what we’re bringing with us so that we can later distinguish lunar chemistry from stuff we brought from Earth,” Graham said.
