Space travel captures imaginations, but beneath the glittering rockets lie some truly sickening facts that most people never hear about. From the way astronauts stay hydrated to the grim possibilities of a body floating forever, these realities make the final frontier feel a lot less glamorous.
Sickening Facts About Space Travel
10 NASA Doesn’t Know What To Do With Astronauts Who Die In Space
NASA admits it has no solid game plan for handling the remains of an astronaut who might die beyond Earth’s atmosphere. The agency never expected a death in orbit, so formal training on corpse management never made it onto the curriculum. Yet, with missions to Mars on the horizon, the question becomes unavoidable.
One theoretical solution—simply releasing the body into the void—runs afoul of United Nations rules that forbid dumping any waste, including human remains, into space for fear of collisions or planetary contamination. Storing the corpse aboard the spacecraft until a return trip is also off the table, because it would jeopardize the safety of the living crew. Some have even floated the idea of using a dead body as fertilizer on a future Martian colony, though it’s unclear whether human tissue would make good compost.
Enter “Body Back,” a concept NASA is developing with the burial firm Promessa. The plan involves sealing the astronaut in an airtight sleeping bag, attaching it to the exterior of the ship, and letting the extreme cold of space freeze the body. As the craft journeys onward, the frozen corpse would vibrate and eventually shatter into fine dust. By the time the vessel returns to Earth, only microscopic particles would remain.
9 Astronauts Drink Recycled Urine
Fresh water is a scarce commodity aboard the International Space Station (ISS). To keep the crew hydrated, NASA relies on the Water Recovery System, introduced in 2009, which captures moisture from sweat, breath, and even urine, then purifies it back into drinkable water.
American astronauts don’t just recycle their own pee; they also process the urine of their Russian counterparts, who have historically refused to reuse their own waste streams. According to Layne Carter, the ISS’s water subsystem manager, the reclaimed water tastes just like bottled water on Earth.
8 Astronauts Lose Muscle And Bone Mass And Suffer From Premature Aging
Microgravity takes a toll on the human body, accelerating the aging process in several ways. Skin becomes thinner, drier, and prone to itching. Meanwhile, muscles and bones deteriorate at alarming rates—about 1 % of muscle mass and up to 2 % of bone density each month spent in orbit.
A six‑month stint aboard the ISS can shave roughly 11 % off the mass of a hip bone. Arteries stiffen as they would in someone two or three decades older, raising the risk of heart disease and stroke. Canadian astronaut Robert Thirsk described feeling like a senior citizen after a six‑month mission, citing weakness, fragile bones, and balance issues. While exercise—typically two hours daily—helps mitigate these effects, the underlying aging process remains an unavoidable side effect of spaceflight.
7 Space Travel Might Be Making Astronauts Infertile
Animal studies suggest that weightlessness could impair reproductive health. Male rats suspended for six weeks in a simulated zero‑gravity environment experienced shrunken testes and a drastic drop in sperm count, effectively rendering them infertile. Female rats fared even worse; after just 15 days in space, their ovaries stopped functioning, the gene responsible for estrogen production became redundant, and egg‑producing cells began to die.
Spaceflight has also been linked to reduced libido. In one experiment, rodents sent into orbit refused to mate, while other researchers argue that the lack of reproduction may be due to stress rather than gravity itself. Interestingly, fish and frog eggs have successfully fertilized in space, though frog embryos never progressed beyond the tadpole stage. Human data is mixed—male astronauts have fathered children shortly after returning, while female astronauts report higher miscarriage rates after missions. NASA has even declined to test sperm counts of returning male crew members for privacy reasons.
6 Most Astronauts Get Space Sick
Even with modern spacecraft, space adaptation syndrome—commonly called space sickness—remains a major headache for NASA. More than half of all astronauts report nausea, headaches, vomiting, and general discomfort during the first days of a mission.
One of the earliest documented cases involved ex‑senator Jake Garn, who began feeling ill before even leaving Earth and returned unable to walk properly. His condition was so severe that his fellow crew members started rating their own symptoms in “Garn units”—one Garn, two Garns, and so on. Although an early‑warning device now alerts astronauts when a bout is imminent, a definitive cure remains elusive.
5 All Astronauts Wear Diapers
The first U.S. space suit overlooked a basic human need: a way to relieve oneself. When Alan Shepard became America’s first astronaut, he was forced to pee inside his suit because engineers feared urine might short‑circuit the suit’s electronics.
To solve the problem, NASA introduced a condom‑like device for male astronauts, but this proved inadequate once women joined the astronaut corps in the 1970s. The agency then rolled out the Disposable Absorption Containment Trunk (DACT), a system designed to manage both urine and feces. By 1988, DACT was replaced with the Maximum Absorbency Garment (MAG)—essentially an adult diaper styled like shorts. Each crew member receives three MAGs per mission: one for launch, one for re‑entry, and a spare.
4 It Might Be A Good Idea To Masturbate In Space
Genitourinary health is a hidden concern for astronauts. Men risk prostatitis, while women are prone to urinary tract infections. Between 1981 and 1998, 23 of the 508 NASA astronauts who ventured into space suffered from such ailments.
The Soviet Union learned this the hard way when cosmonaut Vladimir Vasyutin developed severe prostatitis after just two months aboard Salyut‑7, forcing an early return to Earth. NASA medical advisor Marjorie Jenkins explained that reduced ejaculation can allow bacteria to accumulate in the prostate, leading to infection.
While no official policy mandates sexual activity in orbit, anecdotal evidence suggests it does happen. A Russian cosmonaut once confessed to “making sex by hand” in space, and astronaut Ron Garan has hinted that crew members enjoy some “free time” aboard the ISS. The topic remains taboo, but the underlying health rationale is clear.
3 Emergency Medical Services Are Nonexistent In Space
NASA’s medical kit on the ISS is essentially a first‑aid drawer—nothing more sophisticated than basic drugs and simple tools. If an astronaut develops a serious illness or needs surgery, the only option is to send them home.
NASA has an agreement with Roscosmos to launch emergency Soyuz missions that can retrieve a sick crew member. Because a Soyuz requires a three‑person crew, two healthy astronauts must accompany the patient, inflating costs to hundreds of millions of dollars and adding risk to everyone aboard.
Looking ahead to Mars, the stakes are even higher. NASA’s National Space Biomedical Research Institute (NSBRI) is funding research into compact medical devices capable of handling emergencies like heart attacks or appendicitis far from Earth.
2 Drugs Are Less Effective In Space
Even the medicines that do make it to orbit lose potency. In a study, eight first‑aid kits containing 35 different drugs were split between the ISS and a controlled environment at NASA’s Johnson Space Center. After 28 months, the space‑bound kits showed reduced efficacy, with six drugs liquefying or changing color, compared to only two in the Earth‑based kits.
Researchers attribute the degradation to the constant vibration and radiation exposure in space. To mitigate the issue, NASA replaces the ISS’s drug supply every six months and is exploring new packaging and ingredient formulations for future missions.
1 Carbon Dioxide Poisoning Is A Problem
The International Space Station harbors carbon‑dioxide levels far above Earth’s normal 0.3 mm Hg—reaching up to 6 mm Hg. Elevated CO₂ triggers headaches, irritation, and sleep disturbances, making it a common complaint among crew members.
Unlike on Earth, where exhaled CO₂ diffuses into the atmosphere, the gas forms a cloud above each astronaut’s head. The ISS employs fans to push these clouds away and mix the air, but the concentration still exceeds NASA’s target of 4 mm Hg, let alone the ideal 2.5 mm Hg. Reducing CO₂ further would wear out the fans faster, so engineers continue to search for a more efficient solution before humanity embarks on long‑duration missions to Mars.