The University of Colorado Boulder develops a small gravity simulator for space
– News of July 9, 2019 –
Prolonged weightlessness has a significant impact on human health. Nausea, muscle and bone loss, redistribution of fluids, impaired vision or sensation of loss of taste, for example. After a few weeks of terrestrial orbit aboard the international space station, the astronauts must already think of a re-education for the return to Earth. Space agencies do their best to minimize the problem, for example through cable or elastic exercises, but this is not enough.
This is a crucial aspect if we want to one day project ourselves beyond the Moon. Martian settlers would be in a delicate situation if they could not even bear their own weight when they arrive. Science fiction has solved this problem for a long time by putting huge structures in rotation, rings for example. An artificial gravity can be created by centrifugal effect. Such stations can be seen in 2001, A Space Odyssey. However, it would cost astronomical sums to launch and assemble such structures. So far, we choose to let the astronauts bearing the inconvenience, even giving them medical help upon their return.
This is a situation that a team from the University of Colorado Boulder hopes to change. They designed what is perhaps the smallest artificial gravity system in the world. It could fit in a space station module or in a lunar or martian base. The system is quite simple : a rotary table on which someone is installed in a slightly eccentric position, the feet on a small stop facing outwards. When the table is set in motion, the occupant is pushed against the stop and is thus subjected to forces simulating a more or less severe gravity. On board a spacecraft or a space station, the crew could take a few hours of relay aboard such a device, a stimulation that would be sufficient to greatly reduce bone and muscle losses.
Such a system is not perfect, however. Spending hours in a mini centrifuge could make you very sick, especially if it comes to your mind to turn your eyes to the side. In addition to this device, the university team is also working on acclimation methods. It thinks it is possible to train the brain to ignore distress signals from the inner ear. They formed a group of volunteers through more and more long and fast assignments. After a dozen of them, the participants declared themselves comfortable at rotation speeds of 17 revolutions per minute for prolonged periods.
If this device looks very promising, there are still many questions. What rotation speed would be optimal to counteract the effects of weightlessness ? How long should the sessions be ? What position should the occupant of the mini centrifuge take, sitting or standing ? Let’s hope that the system is compact enough to fit on a space station in the not-too-distant future. In the meantime, the astronauts will have to bear their daily exercises and their difficult return.
Image by NASA