NASA astronauts Sunita “Suni” Williams and Barry “Butch” Wilmore have finally returned to Earth after an unexpected nine-month mission aboard the International Space Station (ISS).
The pair had booked an eight-day orbital mission yet suffered spacecraft malfunctions in their Boeing Starliner spaceship which left them orbiting indefinitely.
Many experts have analyzed extended spaceflight exposure on human biology through extensive discussions.
Science experts were shocked by the significant changes in the physiological conditions of these astronauts throughout their rehabilitation process following which new medical data about their body changes became available through their remarkable pre-against-post flight images.
The return mission of Williams and Wilmore encountered a surprise problem that required their spacecraft to be grounded for re-entry.
Their original ISS mission duration of under a week transformed into nine months after the decision to stay during which they supported laboratory experiments and facility upkeep tasks.
The prolonged spaceflight exposed their bodies to the dangerous condition of microgravity which creates major physiological changes in humans.
People greeted their homecoming joyfully while scientists asked about health consequences of duration in spaceflight.
The prolonged exposure to microgravity results in the development of muscle atrophy together with bone density loss and fluid redistribution which collectively produce various health concerns for astronauts returning from space missions.
The absence of gravity causes astronauts to lose 20% of their muscle tissue during only three weeks in space after which they need complete retraining before returning to Earth.
Astronauts lose 1.5% bone density each month after launch so their bodies become more fragile and develop osteoporosis symptoms.
When fluids move toward the head area it results in facial puffiness and impaired vision together with elevated intracranial pressure that compromises eye health.
A change occurs in the cardiovascular system because reduced gravitational force makes the heart work less and cause slight size reduction in its tissue.
Astronauts face problems with their balance system because their spatial orientation center fails to adapt properly after returning to Earth gravity conditions.
The lengthy period in space has delivered vital knowledge to researchers about the effects that space conditions produce on human physiology throughout an extended period.
Research has revealed that long-duration space flight produces abnormal aging patterns which remain among the most unusual space exploration side effects.
The laws of relativity suggest time behaves differently between situations with varying strength of gravity and speed.
Space travelers at the ISS maintain a speed rate of 28,000 kilometers per hour (17,500 miles per hour) which results in their experience of time being somewhat different from Earth-based people.
The spaceflight experience causes astronauts to experience diminished time passage because of time dilation effects.
Astronauts who stay on the ISS during six months will experience a time dilation effect which slows their aging process by 0.005 seconds relative to individuals on Earth.
Williams and Wilmore spent nine months orbiting space which resulted in their aging behind Earth residents by a total of 0.0075 seconds.
Time dilation can be observed through the discrepancy between NASA astronauts Scott Kelly and his twin Mark Kelly.
NASA astronaut Scott remained in space longer than his twin brother so when the two reunited Scott turned out to be six minutes and five milliseconds younger than Marcus.
Scientific measurement proves that space exposure has a measurable effect of delaying the aging process even though this effect is extremely small.
Space exposure caused visible changes in Williams and Wilmore per NASA images yet their actual biological age remained identical to Earth standards.
Feature Image Credit: (NASA)