Astronaut Bruce McCandless II approaches his most distance from the Earth-orbiting Area Shuttle Challenger on this 70mm picture from Feb. 7, 1984. Credit score: NASA.
On Earth, gravity and acceleration are elementary cues that assist people orient themselves and decide how far they’ve traveled. Nonetheless, within the distinctive surroundings of space, these cues are absent or altered, difficult astronauts’ capacity to navigate and transfer successfully.
Recent research, revealed March 13 in Nature’s npj Microgravity, explores how the human physique adjusts to a microgravity surroundings, reminiscent of that skilled on the Worldwide Area Station (ISS). The examine, carried out by researchers from York College in collaboration with NASA and the Canadian Area Company, reveals that regardless of the dearth of conventional gravitational cues, astronauts preserve a surprisingly sturdy capacity to estimate distances traveled primarily based on visible cues alone.
These findings are a small however key step towards making certain astronaut security and operational effectivity in space — and so they could even provide insights into managing age-related steadiness points on Earth.
Does weightlessness have an effect on spatial consciousness?
When aboard the ISS, orbiting some 250 miles (400 kilometers) above Earth’s floor, astronauts stay and work in a state of steady free-fall, creating what is called a microgravity surroundings. This distinctive setting gives researchers with a uncommon alternative to check human perceptions underneath situations which can be unattainable on Earth.
“It has been repeatedly proven that the notion of gravity influences perceptual talent,” mentioned Laurence Harris, a imaginative and prescient and movement notion knowledgeable at York College, in a press release. “Essentially the most profound approach of wanting on the affect of gravity is to take it away, which is why we took our analysis into space.”
“Folks have beforehand anecdotally reported that they felt they had been shifting sooner or additional than they actually had been in space, so this supplied some motivation to truly document this,” Harris mentioned.
Harris’s curiosity led to a complete examine involving 12 astronauts — six males and 6 girls — who carried out spatial exams utilizing a digital actuality (VR) headset earlier than, throughout, and after their time aboard the ISS. The researchers discovered that regardless of not feeling the acquainted power of gravity, astronauts largely maintained their capacity to sense how far they traveled.
Astronauts can nonetheless precisely decide distance traveled
“Based mostly on our findings,” Harris mentioned, “it appears as if people are surprisingly in a position to compensate adequately for the dearth of an Earth-normal surroundings utilizing imaginative and prescient.”
The implications of those findings prolong past educational curiosity. They immediately influence the security and operational capabilities of space crews. The power to evaluate distances precisely in an surroundings the place typical cues are absent is important for avoiding hazards and shortly responding to emergencies.
“On quite a lot of events throughout our experiment, the ISS needed to carry out evasive maneuvers,” mentioned Harris. “Astronauts want to have the ability to go to secure locations or escape hatches on the ISS shortly and effectively in an emergency. So, it was very reassuring to seek out that they had been really ready to do that fairly exactly.”
Because of the packed schedules that the astronauts confronted when arriving on the ISS, the examine didn’t take a look at the astronauts through the first few days of their flights. Nonetheless, Harris mentioned, “it’s nonetheless a excellent news message as a result of it says that no matter adaptation occurs, occurs in a short time.”
Implications on growing older and steadiness
Of their examine, the researchers additionally briefly talk about the doable terrestrial implications of their space-based findings, significantly associated to growing older and steadiness. As a result of the examine signifies astronauts can adequately estimate self-motion, it means that steadiness issues related to previous age is probably not associated to the vestibular system.
“It means that the mechanism for the notion of motion in older folks needs to be comparatively unaffected,” mentioned Harris, “and that the problems concerned in falling is probably not a lot by way of the notion of how far they’ve moved, however maybe extra to do with how they’re in a position to convert that right into a steadiness reflex.”
Though way more analysis continues to be wanted on the subject, this examine does trace at potential new avenues for growing therapies and preventions for steadiness issues among the many aged, who’re more and more susceptible to falls as world populations age.
The significance of space well being analysis
This investigation marks the primary of a collection of three research aimed toward understanding the vary of perceptual modifications astronauts expertise when residing in a microgravity surroundings. Future analysis will discover how microgravity influences different perceptual talents, reminiscent of estimating physique orientation and object sizes.
“We’ve had a gentle presence for near 1 / 4 century in space,” mentioned Harris, “and with space efforts solely rising as we plan to return to the Moon and past, answering health-and-safety questions solely turns into extra necessary.
