There is a risk that the lunar soil is combined with terrestrial microbes and this could start some of the future scientific missions.
Terrestrial microbes brought to the moon, can survive in the permanently shaded regions (PSR permanently shadowed regions), like polar areas who never receive sunlight due to the slightest axial inclination of the satellite? This is the application at the center of a recent study presented at the 56th Conference on the Lunar and Planetary Sciences.
This research could revolutionize our understanding of the extreme environments in which life could exist in the sun system. John Moores, associate professor at the Center for Research in Earth Sciences and the York University space and the main author of the Research, explained the results obtained to Universe Today e The implications for the human exploration of the Moon and the risk of microbiological contamination.
How this study was born. «In 2019 I participated in a study on any Moon microbial contamination Through space vehicles, led by Dr. Andrew Schuerger of the University of Florida », says Moores. «At the time we had not considered the RDPs due to the complexity of their environmental modeling. However, in the following years, my former student, Dr. Jacob Kloos of the University of Maryland, developed a sophisticated Moon lighting model that allowed us to explore this hypothesis».
Thanks to the growing interest in the exploration of the RDPs, the researchers decided to deepen the theme, creating a series of simulations for evaluate whether the poor exposure to ultraviolet rays and the low temperatures inside the Shackleton and Faustini craters could allow the survival of the microbes.
Hospitable environment for microbes. Shackleton and Faustini craters are among the Objectives of NASA Artemis Missions Missions. These sites have not received sunlight for billions of years due to the axial inclination of the moon, equal to only 1.5 degrees compared to the sun. This creates conditions of cold which, according to the researchers, could preserve terrestrial microbes For long periods. “In the void of space, microbes are usually eliminated by heat and ultraviolet rays,” explains Moores, “but in the RSR, theabsence of light and very low temperatures could protect them. They are unlikely that they can metabolize, grow or replicate, but Some spores may remain vital for decades before being destroyed by the effects of the void. In addition, the organic molecules of their cells could survive even longer ».
If they ended up in the instruments of astronauts could replicate inside the outposts that will be built on the moon or provide false information about the presence of life forms.
But everything would be very interesting because it would allow to affirm that on planets like Mars, in areas often in the shade, living organisms may have preserved in the event that there was life in the past.
The risk of contamination. The lunar RODs are crucial for human exploration, especially for the presence of potentials Water ice bags that could be used to obtain drinking waterfuel and oxygen. However, each space mission brings with it the risk of microbiological contamination, risking to affect scientific analyzes. “While we can carefully sterilize robotic spatial vehicles, it is much more difficult to decontaminate equipment and spatial suits of astronauts,” warns Moores. “The human beings naturally transport a great variety of microbeswhich could settle in the RDPs and remain preserved for a long time ».
To prevent this risk, the NASA Planetary Protection Office imposes rigorous sterilization protocols before launch And it monitors any contamination of returning from space. However, the question remains: How far could this contamination influence future scientific analyzes? “If we want to study ice in the RDPs to understand its origins and its composition, we must minimize terrestrial contamination,” Moores underlines. “The organic molecules present could provide clues to the history of the Solar System, but the reliability of the data will depend on the absence of external contaminants”.
How do microbes arrive in the PSRs? The moon has been the target of numerous impacts, both natural and artificial. “The probability that there is already a terrestrial microbial contamination in the PSRs is low, but not nothing,” observes Moores.
Several space probes have crashed on the lunar surface, including the Ranger mission and, more recently, the NASA LCROSS probe, which in 2009 has The Cabeus crater, a PSR located near the South Lunar Pole impacted. «Even if these impacts have occurred at high speed, some studies suggest that A reduced number of spores could survive», Says Moores. “If some microbes were resisted the impact, they may have spread widely in the RDPs.”
What happened to the Lunar Tardigrades? The Beresheet mission, an Israeli space probe launched in February 2019, had the aim of making a soft landing on the moon, but unfortunately, on April 11, 2019, during the descent phase, it suffered a fault that caused the crash on the lunar surface.
On board the probe were present Thousands of dehydrated Tardigradesknown for their extraordinary survival capacity in extreme conditions, much larger organisms of bacteria.
Even if subsequent studies have indicated that, despite the resistance of the Tardigradi, it is unlikely that they survived the violent impact of the probe with the moon, however the possibility that they survived in a sort of hibernation exists.
