As humanity inches closer to becoming a multiplanet species, it’s worth knowing the fascinating things that happen to our bodies when we leave Earth’s comforting gravity.
Fascinating Things About the Human Body in Space
10 Space Adaptation Syndrome
When the pull of Earth’s gravity disappears, many astronauts experience space sickness—officially called Space Adaptation Syndrome. It feels like motion sickness on steroids, with headaches, disorientation, severe discomfort, and sometimes vomiting or vertigo. Roughly half of all space‑faring humans get the bug, so you’ll be in good company. The culprit isn’t the absence of gravity itself but the sudden shift in gravitational forces that throws your inner balance off.
The good news? It usually clears up after a few days as your body learns to cope with weightlessness. Until then, you’ll need a transdermal dimenhydrinate anti‑nausea patch to keep the puke in check. Vomiting inside a space suit isn’t just messy—it can obstruct vision, compromise breathing, and become life‑threatening in the zero‑gravity environment.
9 What’s That Smell?
Space may look like a silent void, but it carries a surprisingly robust aroma. Astronauts report that the air inside the International Space Station smells like seared steak, burning metal, and gunpowder—a decidedly masculine blend. Don Petite summed it up as “metallic.” NASA even hired chemist Steven Pierce to recreate the scent for training simulations, though nobody seems to have marketed it for everyday use yet.
8 You’re Gonna Lose Your Fingernails
In the microgravity environment, bulky space‑glove cuffs can restrict blood flow to the fingertips. The resulting pressure often leads to fingernail delamination—basically, the nail separates from the nail bed and may fall off. A recent study found 22 astronauts reporting nail loss, and some have even pre‑emptively ripped off their own nails before a spacewalk to avoid the surprise.
7 No Snoring
Weightlessness also means a quieter night for your crewmates. With gravity out of the picture, the tongue and soft palate stay relaxed, eliminating the airway blockage that causes snoring on Earth. In other words, you’ll be at least 20 % less annoying to your fellow astronauts while you soak in the metallic scent of space.
6 Vision Problems
Extended stays in orbit can blur your sight. The fluid shift toward the head flattens the back of the eyeball and nudges the retina, leading to temporary vision distortion. About 23 % of astronauts on short missions and nearly half on long missions report these issues. The pressure also produces “cosmic ray flashes”—spontaneous light bursts that feel like a rave in your retina.
5 Effects On Your Muscles
Floating around may look effortless, but it’s a workout for the wrong muscles. In microgravity, the lower body experiences bone loss and muscle atrophy, while the heart can shrink slightly because it doesn’t need to pump blood against gravity. So all those Earth‑bound complaints about not exercising actually reflect the hard work your muscles do just to fight Earth’s pull.
4 Prepare To Be Taller
One of the more fun side effects is a temporary boost in height. The vertebrae separate slightly in zero‑gravity, adding up to about three percent to your stature—think a few extra inches, enough to channel your inner Joey Ramone. Once you return to Earth’s pull, your spine compresses back to normal.
3 Your Unprotected Body In The Vacuum Of Space
If you ever find yourself floating suit‑less in the vacuum, you have about 15 seconds before the oxygen in your bloodstream is exhausted. Holding your breath is a fatal mistake—your lungs will over‑expand and rupture, spilling air into your circulatory system. After ten seconds, bodily fluids begin to vaporize, your tongue’s saliva can boil, and you’ll experience rapid decompression symptoms like sunburn and “the bends.” You won’t freeze instantly, but you’ll either mummify or become an icy statue over time.
2 Space Radiation
Orbiting the Earth exposes you to roughly ten times the radiation you’d encounter on the ground. Without the protective blanket of our atmosphere, cosmic rays can damage the nervous system, leading to altered cognition, reduced motor function, and behavioral changes. Radiation sickness may bring nausea, vomiting, loss of appetite, and fatigue, and long‑term exposure raises the risk of cancer and other diseases.
1 Space Euphoria
Beyond the physical quirks, many astronauts describe a profound sense of euphoria and spiritual awe. Charlie Duke recalled being overwhelmed by the certainty that his view was part of a universal order, while Edgar Mitchell felt a tranquil, almost transcendent clarity. Gene Cernan sensed a presence larger than himself, and Rusty Schweickart described feeling “part of everyone and everything” as Earth spun below. The experience can reshape perspectives and leave travelers forever changed.