Japanese scientists have designed a conic artificial gravity habitat, taking humanity another step closer to space colonisation.
“Humanity is now moving from the era of 'staying' in space to the era of 'living' on the Moon and Mars,” the Kyoto University’s Human Spaceology Center writes in a statement, announcing their project with major construction firm Kajima to design an artificial gravity facility in space.
One of the primary obstacles to making space livable for humans is microgravity, or the sensation of being almost weightless. The upcoming facility offers a solution to this issue.
According to NASA, astronauts who have spent considerable time in space frequently return with bone loss – an average of 1 to 1.5 percent of mineral density is lost for each month spent during spaceflight. Astronauts also lose muscle mass faster without Earth's gravity.
Another side effect of microgravity is fluid shifts, as fluids in the human body shift upward without gravity, putting pressure on the eyes. Kidney stones and decline in heart function can be expected as well.
Astronauts also struggle with their blood pressure at the risk of fainting, and experience changes in sensorimotor skills such as balance and hand-eye coordination due to trouble in adjusting in between different gravity fields.
Scientists have been trying to prevent these issues through several interventions, ranging from medicine and fine motor skills testing to diet and exercise for muscle loss and compression cuffs worn on the thighs to keep the fluids down.
Nevertheless, none of these mechanisms competes with the potential of creating Earth-like gravity in space as such a measure would eliminate the adverse effects of microgravity from scratch.
Eliminating the adverse effects of microgravity
“As the idea of living in space becomes more realistic, the problem with the low gravity, which I intuitively became aware of when I was a child, is an issue we must overcome," says Takuya Ono, a project associate professor with the Human Spaceology Center and a senior researcher at Kajima.
The key element of the plan is constructing “artificial gravity living facilities” to become an infrastructure for life in space. These facilities are planned to be built on the Moon and Mars, respectively called LunarGlass and MarsGlass.
The structures, called “The Glass,” are approximately 4 metres (1,300 feet) tall. They are designed in a conic shape and complete a full rotation every 20 seconds.
Researchers suggest that the shape and rotation combined will make Earth-like conditions possible in space by using centrifugal force, providing normal gravity and thus eliminating the adverse effects of microgravity on humans.
That is “the core technology for human space exploration,” says the Kyoto University, while also suggesting that the prospect of future generations to be born in space make this technology essential for sustaining human life in space.
“Without gravity, mammals may not be able to give birth successfully,” the center suggests, adding that even then, the normal course of development would be hindered.
“We believe that people should live in the facility on a daily basis and enjoy the low gravity of the Moon and Mars and the weightlessness of space only when they are working, conducting research, or enjoying leisure,” it continues, aiming to minimise exposure to microgravity.
The Earth-like conditions provided by the facilities would also enable residents to go back to Earth “at any time” with minimal side effects.
“Core Biome” and transportation
Two other pillars of the plan are transferring natural capital to space and establishing an interplanetary transportation system.
The researchers are planning to “extract” a reduced biome from the Earth’s ecosystem to be transferred to space as a “core biome” to make life as we know it possible for future colonies in space. They first aim to identify a “selected core biome” which is the “minimum biome necessary for (human) migration”.
They are aiming for facilities that look as much like the Earth as possible, complete with bodies of water and trees.
Also predicting that people will travel for business and tourism in a future space colony, the researchers have contemplated the need for an interplanetary transportation system which will keep gravity constant, minimising the adverse effects of microgravity during long-distance travel.
Called the Hexatrack, this orbital track system will operate between the Earth, Moon, and Mars, with stations constructed on each one respectively called the Terra Station, Lunar Station and Mars Station.
“We are convinced that the three pillars of our proposal are not found in the development plans of other countries, and that they are the core technologies that are essential to ensure the implementation of human space migration in the future,” says Yosuke Yamashiki, director of the center, according to the statement from the Kyoto University.
Researchers estimate that the construction of The Glass facilities is only feasible 100 years into the future. However, a prototype facility is planned to be constructed on the lunar surface by 2050.