Humans could move to this floating asteroid belt colony in the next 15 years

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https://www.livescience.com/megasatellite-colony-ceres-oneill-cylinder.html

Humans could move to this floating asteroid belt colony in the next 15 
years, astrophysicist says
By Brandon Specktor - Senior Writer 2 days ago

Should we build a 'megasatellite' of human habitats around the dwarf 
planet Ceres? It's more plausible than it sounds.


This NASA illustration depicts an O'Neill Cylinder: a floating human 
habitat orbiting an alien planet. A new paper proposes building a 
mega-colony of them around the dwarf planet, Ceres.
(Image: © Rick Guidice courtesy of NASA)

Now more than ever, space agencies and starry-eyed billionaires have 
their minds fixed on finding a new home for humanity beyond Earth's 
orbit. Mars is an obvious candidate, given its relatively close 
proximity, 24-hour day/night cycle and CO2-rich atmosphere. However, 
there's a school of spacefaring thought that suggests colonizing the 
surface of another planet — any planet — is more trouble than it's worth.

Now, a new paper published Jan. 6 date to the preprint database arXiv 
offers a creative counter-proposal: Ditch the Red Planet, and build a 
gargantuan floating habitat around the dwarf planet Ceres, instead.

In the paper, which has not yet been peer-reviewed, astrophysicist Pekka 
Janhunen of the Finnish Meteorological Institute in Helsinki describes 
his vision of a "megasatellite" of thousands of cylindrical spacecrafts, 
all linked together inside a disk-shaped frame that permanently orbits 
Ceres — the largest object in the asteroid belt between Mars and 
Jupiter. Each of these cylindrical habitats could accommodate upwards of 
50,000 people, support an artificial atmosphere and generate an 
Earth-like gravity through the centrifugal force of its own rotation, 
Janhunen wrote. (This general idea, first proposed in the 1970s, is 
known as an O'Neill cylinder).

Related: Populating a Mars base will be dangerously unsexy

But why Ceres? Its average distance from Earth is comparable to that of 
Mars, Janhunen wrote, making travel relatively easy — but the dwarf 
planet also has a big elemental advantage. Ceres is rich in nitrogen, 
which would be crucial in developing the orbiting settlement's 
atmosphere, Janhunen said (Earth's atmosphere is roughly 79% nitrogen.) 
Rather than building a colony on the surface of the tiny world — Ceres 
has a radius roughly 1/13th that of Earth — settlers could utilize space 
elevators to transfer raw materials from the planet directly up to their 
orbiting habitats.

CLOSE
This orbital lifestyle would also address one of the biggest caveats 
Janhunen sees in the idea of a Martian surface colony: the health 
impacts of low gravity.

"My concern is that children on a Mars settlement would not develop to 
healthy adults (in terms of muscles and bones) due to the too-low 
Martian gravity," Janhunen told Live Science in an email. "Therefore, I 
searched for [an] alternative that would provide [Earth-like] gravity 
but also an interconnected world."

Even so, Janhunen's proposal comes with its own caveats that could work 
against a successful Ceres colony, an outside researcher pointed out.


This NASA illustration shows what the interior of an O'Neill Cylinder 
could look like. Each habitat would have an artificial atmosphere, 
Earth-like gravity and a mix of urban and agricultural space.

This NASA illustration shows what the interior of an O'Neill Cylinder 
could look like. Each habitat would have an artificial atmosphere, 
Earth-like gravity and a mix of urban and agricultural space. (Image 
credit: Rick Guidice courtesy of NASA)

Welcome to disk-world
According to Janhunen's proposal, each cylinder of the Ceres 
megasatellite would produce its own gravity through rotation; each 
cylindrical habitat would measure about 6.2 miles (10 kilometers) long, 
have a radius of 0.6 miles (1 km) and complete a full rotation every 66 
seconds to generate the centrifugal force needed to simulate Earth-like 
gravity.

A single cylinder could comfortably hold about 57,000 people, Janhunen 
said, and would be held in place next to its neighboring cylinders 
through powerful magnets, like those used in magnetic levitation.

Janhunen's megasatellite would include a disk of interconnected habitat 
cylinders, flanked on both sides by massive mirrors to angle sunlight 
into the colony.

That interconnectedness points to the other big advantage of 
megasatellite living, Janhunen said: New habitat cylinders could be 
added onto the edges of the colony indefinitely, allowing for near 
unlimited expansion.

"Mars' surface area is smaller than Earth's, and consequently it cannot 
provide room for significant population and economic expansion," 
Janhunen told Live Science. A Ceres colony, on the other hand, "is 
growable from one to millions of habitats."

Seeing the light
Beyond the cylinders and their massive disk frame, the colony's main 
features will be two enormous glass mirrors, angled at 45 degrees 
relative to the disk in order to reflect just enough natural sunlight 
into each habitat. Part of each cylinder will be devoted to growing 
crops and trees, planted in a 5-foot-thick (1.5 meters) bed of soil 
derived from raw materials from Ceres, Janhunen wrote. The natural 
sunlight should keep them growing strong. (The "urban" part of each 
cylinder, meanwhile, would rely on artificial light to simulate an 
Earth-like day/night cycle. Janhunen does not stipulate where the 
settlement's oxygen comes from.)

Related: 10 interesting places in the solar system we'd like to visit

This society of floating, cylindrical utopias may sound a bit 
outlandish, but it has its proponents. In 2019, Jeff Bezos (Amazon CEO 
and founder of the private space company Blue Origin) spoke at a 
Washington, D.C., event about the merits of building "O'Neill colonies" 
similar to the one Janhunen describes here. Bezos was skeptical that 
such a colony could exist in our lifetime, asking the audience, "How are 
we going to build O'Neill colonies? I don't know and no one in this room 
knows."

However, Janhunen is more optimistic. In an email to Live Science, he 
said that the first human settlers could start heading to Ceres within 
the next 15 years.

The future is bright when you live in a habitat cylinder.

The future is bright when you live in a habitat cylinder millions of 
miles from Earth. (Image credit: Don Davis courtesy of NASA)

Next year on Ceres?
Manasvi Lingam, an assistant professor of astrobiology at the Florida 
Institute of Technology who studies planet habitability, said that the 
Ceres proposal presents a "plausible alternative" to colonizing the 
surface of Mars or the Moon, but still lacks some key considerations.

"I would say there are three main caveats," Lingam, who was not involved 
with the paper, told Live Science. "The first is a question of other 
essential elements, other than nitrogen."

One key element that isn't mentioned in the paper is phosphorus, Lingam 
said. The human body relies on phosphorus to create DNA, RNA and ATP (a 
vital form of energy storage in cells). All organisms on Earth — 
including any plants colonists might hope to grow in their floating 
habitats — need it in one way or another, but Janhunen's proposal 
doesn't address where or how this critical element would be obtained.


The second caveat is the technology, Lingam said. Collecting nitrogen 
and other raw materials from Ceres would require mining the planet's 
surface and extracting those crucial elements from the rocks themselves. 
This operation likely wouldn't be possible without a fleet of autonomous 
mining vehicles ready to deploy on Ceres, plus satellites to guide them 
to the most viable nutrient-rich deposits. The idea is plausible, Lingam 
said, but technologically, we aren't there yet; just recently (on Jan. 
15), a NASA Mars robot was declared dead after it failed to bury itself 
just 16 feet (5 meters) into the Martian surface, terminating a two-year 
mission.

Those technological limitations point to Lingam's third caveat, which is 
the proposed time frame. Janhunen's proposal suggests that the 
megasatellite's first cluster of orbiting habitats could be completed 22 
years after mining begins on Ceres. But this estimate assumes the 
settlement's available power supply grows exponentially each year, 
beginning immediately and never stalling due to technological or 
logistical problems. That estimate "isn't inconceivable," Lingam said, 
but shouldn't be taken for granted.

"That timescale of 22 years might be the lower bound under optimal 
conditions, but I'd argue that the real timescale could be a lot 
longer," Lingam said.

Originally published on Live Science.

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