Solar powered lunar arch proposed as “modern global insurance policy”

The ambitious project proposed by a team at the University of Arizona aims to preserve humanity – and animal, plant and fungal species – in the event of a global crisis.

University of Arizona researcher Jekan Thanga draws inspiration from an unlikely source: the biblical story of Noah’s Ark. Instead of two of each animal, however, his solar ark on the moon is said to store cryogenically frozen seeds, spores, sperm, and eggs. samples of 6.7 million terrestrial species.

Thanga and a group of her undergraduate and graduate students describe the concept of the lunar arch, which they call a “modern global insurance policy,” in an article featured over the weekend at the IEEE Aerospace conference (see video below).

“Earth is naturally a volatile environment,” said Thanga, professor of aerospace and mechanical engineering at the UArizona College of Engineering. “As humans, we had a close call about 75,000 years ago with the supervolcanic eruption of Toba, which caused a cooling period of 1,000 years and, according to some, corresponds to an estimated drop in the human diversity. Because human civilization has such a large footprint, if it were to collapse it could have a cascading negative effect on the rest of the planet.

Climate change, he added, is another concern: if sea level continues to rise, many dry places will go underwater – including the Svalbard Seedbank, a structure in Norway that contains hundreds of thousands of seed samples to protect against accidental loss of biodiversity. Thanga’s team believe that storing samples on another celestial body reduces the risk of biodiversity loss if an event causes the Earth to be completely wiped out.

Totally tubular

Scientists discovered a network of about 200 lava tubes just below the moon’s surface in 2013. These structures formed billions of years ago when streams of lava melted through soft rock underground. , forming underground caverns. On Earth, lava tubes are often similar in size to subway tunnels and can be eroded by earthquakes, plate tectonics, and other natural processes. This network of lunar lava tubes is about 100 meters in diameter. Intact for about 3 to 4 billion years, they could provide shelter from solar radiation, micrometeorites and changes in surface temperature.

The idea of ​​developing a lunar base, or human settlement on the moon, has been around for hundreds of years, and the discovery of the lava tube has renewed enthusiasm in the space community for the concept. But the moon is not exactly a hospitable environment where humans can spend long periods of time. There is no water or breathable air, and it is about minus 25 degrees Celsius, or minus 15 degrees Fahrenheit. It is not a very hectic place either.

On the other hand, these same characteristics make it an ideal place to store samples that must remain very cold and undisturbed for hundreds of years at a time.

Building a Lunar Arch is no small feat, but, based on a few “quick calculations on the back of the casing,” Thanga said it wasn’t as overwhelming as it sounds. Transporting around 50 samples of each of 6.7 million species would require around 250 rocket launches. It took 40 rocket launches to build the International Space Station.

“It’s not a big deal,” Thanga said. “We were a little surprised about this.”

Cryogenics and quantum levitation

The mission concept builds on another project Thanga and his group had previously proposed, in which miniature flying and jumping robots called SphereX enter a lava tube in teams. There they collected samples of regolith, or loose dust and rock, and gathered information about the arrangement, temperature, and composition of the lava tubes. This information could inform the construction of the lunar base.

The team’s model for the underground arch includes a set of solar panels on the moon’s surface that would provide electricity. Two or more elevator shafts would lead to the facility, where the Petri dishes would be housed in a series of cryogenic storage modules. An additional freight elevator shaft would be used to transport building materials so that the base could be extended inside the lava tubes.

To be cryopreserved, seeds must be cooled to minus 180 C (minus 292 F) and stem cells stored at minus 196 C (minus 320 F). As a reference for how cold it is, the Pfizer COVID-19[feminine le vaccin doit être conservé à moins 70 C, ou moins 94 F.Le fait que les tubes de lave soient si froids et que les échantillons doivent être encore plus froids, signifie qu’il y a un risque que les parties métalliques de la base puissent geler, se coincer ou même froid- souder ensemble. Sur Terre, les compagnies aériennes commerciales cessent de fonctionner lorsque les températures au sol atteignent moins 45 à moins 50 C (moins 49 à moins 58 F).

Cependant, il existe un moyen de profiter des températures extrêmes en utilisant un phénomène d’un autre monde appelé lévitation quantique (voir la vidéo ci-dessous). Dans ce processus, un matériau supraconducteur cryo-refroidi – ou un matériau qui transfère l’énergie sans perdre de chaleur, comme le fait un câble traditionnel – flotte au-dessus d’un puissant aimant. Les deux pièces sont verrouillées ensemble à une distance fixe, donc partout où va l’aimant, le supraconducteur suit.

“It’s like they’re locked with ropes, but invisible ropes,” Thanga said. “When you get to cryogenic temperatures, strange things happen. Some of them look like magic, but are based on principles of physics that have been proven and tested in the laboratory to the limit of our understanding.

The team’s arch design uses this phenomenon to float sample shelves above metal surfaces and allow robots to navigate the facility over magnetic tracks.

There is much more research to be done on how to build and operate the ark, from studying how stored seeds might be affected by a lack of gravity, to developing a plan for basic communications with Earth.

“What amazes me about projects like this is that they give me the impression that we are getting closer to becoming a space civilization, and to a not-so-distant future where humanity will have bases. on the moon and MarchSaid Álvaro Díaz-Flores Caminero, a doctoral student from Arizona who is leading the thermal analysis for the project. “Multidisciplinary projects are difficult because of their complexity, but I think the same complexity is what makes them beautiful.”