With all the logistics involved, it is unlikely that humanity will ever see our way outside the Solar System to colonize colonies of exoplanets. But it is not so far from settling elsewhere within the Solar System.
NASA is planning an outpost on the Moon. Crew missions to Mars are not far away. Heck, even some of us already live off the planet (albeit temporarily) on the International Space Station.
So is there any other place in the Solar System that people could make our home? Well, according to physicist and astrobiologist Pekka Janhunen from the Finnish Meteorological Institute in Finland, the dark planet Ceres is not entirely unbelievable.
Ceres is an interesting piece of rock. It hangs out in the asteroid belt between Mars and Jupiter, and with its 952-kilometer (592-mile) diameter, it is considered to be both the most recognizable asteroid in Earth. -Solar system, and the only planet deep closer to the Sun than Neptune.
Why Ceres? It kicks a lot of desirable boxes, Janhunen thinks.
“The motivation,” he writes in an introductory paper published on arXiv, “is to have a settlement with artificial gravity that allows it to grow beyond the Earth’s living space, and at the same time providing easy travel within a settlement for the residents and a reasonably low population density of 500 [people per] square kilometers. “
He says that Mars and the Moon may not be the best places for human colonies, because their natural weight is so different from that of Earth. We know that astronauts have health problems when they return to Earth from a low or zero-G environment; we have little idea of the impact of growth to maturity in low weight.
An alternative to the colonial planetary colony model is an artificial space, orbiting the sun – a space station spinning to generate a centrifugal force sufficient to identify one: Gravity of the Earth.
This would be very difficult too. If the population grows too large for one settlement, several settlements may be required. If multiple colonies are in orbit around the sun, they could move apart, creating other problems, such as inter-settlement travel. If they are moving a common body, avoiding bumps will be a problem.
Janhunen’s solution is very neat, realistically, at least in concept: use Ceres as a base around which the settlement nodes could spin an orbit, connected by a fixed frame.
This would not only solve the problem of holding the settlement nodes together without being able to collide, but it would also solve the problem of materials neatly, as they could be collected directly from the planet. deep. Nitrogen is especially important, Janhunen said, because it makes up so much of the Earth’s atmosphere.
But we also know that Ceres is very salty, and recent research suggests that there may be a lot of water under the surface as well. Solar panels on the surface of the deep planet could power a space-to-satellite elevator.
“Building the materials from Ceres is energy-efficient compared to processing them into habitats, if a space elevator is used,” explains Janhunen. “Because Ceres has low gravity and circulates to relatively quickly, it is possible to lift the space elevator. “
A radiation shield, he said, could be built from 80 percent silicate regolith (rock from Ceres) and water. The habitats would be divided into rural and urban areas, with a ground depth of 1.5 meters up to 4 meters as required for trees and gardens.
(P. Janhunen, arXiv, 2020)
Because Ceres is so far from the sun, mirrors could be used to direct sunlight towards the habitat, for growing crops, for lighting, and for solar power. These mirrors would be bent on one side of the satellite in the shape of a disk, similar to a make-up material, and could be adjusted to collect maximum sunlight as the deep planet moves around the sun. .
“We use disc geometry for the megasatellite because its symmetry eliminates tidal torque so that reversing wheels are not required to maintain feedback,” Janhunen writes.
“The areas are illuminated by natural sunlight. Sunlight is collected on the disk by two planar mirrors inclined at a 45-degree angle and focused to the intensity you want with parabolic mirror. “
This could be grown, as needed, by simply adding more habitats at the edges of the first, to millions of potential habitats, for a way of life. could be even better than life on Earth.
After all, there would be no natural disasters or unpleasant weather, and its politeness would mean that it could just keep growing with the population. In principle, Ceres could support, Janhunen believes, 10,000 times the population of Earth.
Of course, it’s all very speculative, but it hasn’t been confirmed yet. Moreover, Janhunen notes that artificial orbital gravity remains a goal that has not yet been achieved.
For that reason, space lifts, large mirrors, and a radiation shield are enough to protect a space colony. Orbital simulations for Ceres, and transport logistics that many humans are beyond Mars, are also reasons that have not been considered.
However, once these kinks are extracted, it would only take about 22 years to build a human satellite in orbit around Ceres, Janhunen estimates.
“Perhaps the overall problematic level of implementation of this project is similar to that of Mars,” he writes.
“The delta-v and the journey to Ceres are longer, but on the other hand one avoids coming to a planet and the weather and dust in the atmosphere. On Ceres it takes a little effort to get the materials into orbit. use the elevator, but it is energy cheap. Once the materials in Ceres orbit are high, the thermal environment is uniform and energy is readily available due to the lack of eclipses. “
Definitely worth thinking about, right?
Janhunen’s paper, written under the framework of the Finnish Center of Excellence in Sustainable Place Research, is available on arXiv.
H / T: Phys.org