In space, an astronaut can grow up to 2 inches taller due to the lack of gravity compressing their spine. The smell inside the space station is often described as a mix of burnt steak and welding fumes. Astronauts have to strap themselves down to sleep so they don’t float away while resting.

A sneeze in a space helmet is one of the most annoying things for any astronaut—it just hangs there. Space suits weigh about 300 pounds on Earth but feel nearly weightless in orbit. Astronauts on the ISS orbit Earth roughly every 90 minutes, so they see 16 sunrises a day.

Some astronauts bring musical instruments to space—guitars, flutes, and even a didgeridoo have made the trip. The first food eaten on the moon was bacon cubes and sugar cookies. No one can burp in space the same way they do on Earth because of how gas behaves in microgravity.

When you cry in space, the tears don’t fall—they just stick to your eyes and float around. Astronaut training includes learning how to survive in the desert, jungle, and ocean. The longest single spaceflight by an astronaut lasted 437 days.

You can’t use regular pens in space—they leak or don’t work upside down. That’s why astronauts use pressurized pens. NASA has a special underwater lab where astronauts train for spacewalks. A Russian astronaut once played chess against people on Earth from orbit.

The Apollo astronauts left 96 bags of human waste on the moon. Space toilets use air flow instead of water to get the job done. An astronaut's bones lose density in space due to lack of gravity, which can be dangerous long-term.

Haircuts in space involve a vacuum to catch floating hair clippings. The first American woman in space was Sally Ride in 1983. Astronaut gloves are so bulky that picking up a coin would be nearly impossible.

In space, hot air doesn’t rise, so ventilation is key to avoid pockets of CO₂ forming. Before launch, astronauts often eat steak and eggs—it’s low in fiber to reduce the need for bathroom breaks. Spacecraft windows are so strong they can handle small debris traveling faster than a bullet.

The first space selfie was taken by Buzz Aldrin in 1966 during a Gemini mission. Astronauts' sense of taste gets dull in space, so they often crave spicy or bold flavors. You can’t whistle properly in a spacesuit—the helmet blocks the sound vibrations.

When astronauts return to Earth, they often need help walking because of muscle loss. The ISS is about the size of a football field and weighs around 420 tons. To wash their hair, astronauts use no-rinse shampoo and a towel.

There are no showers in space, so astronauts wipe down with cloths and rinse-free solutions. An astronaut suit costs around \$12 million to make. Buzz Lightyear’s name was inspired by astronaut Buzz Aldrin.

The first living creature in space was a dog named Laika from the Soviet Union. Space can cause vision problems—some astronauts return needing glasses. Astronauts often lose their sense of smell temporarily in orbit.

Velcro is a favorite item on the ISS—it keeps everything from tools to toothbrushes in place. Spacewalks are mentally and physically exhausting, often lasting six to eight hours. The American flag planted on the moon is probably white by now, bleached by UV rays.

Astronauts experience “space headaches” caused by shifting body fluids. You can see the Great Wall of China from space—sort of. It’s hard to spot without help. Some astronauts say the view of Earth from orbit changed their perspective on life.

There’s a tradition of astronauts listening to specific wake-up songs on mission mornings. Food packaging in space is specially designed to prevent crumbs from floating. Astronauts train in virtual reality to simulate space station tasks.

The ISS travels at about 17,500 miles per hour—that's fast enough to circle Earth in 90 minutes. Some astronauts bring family mementos to space like wedding rings or small toys. The Moon smells like gunpowder, according to Apollo astronauts.

The first woman to walk in space was Soviet cosmonaut Svetlana Savitskaya in 1984. Spacewalks are also called EVAs—short for Extra-Vehicular Activity. Astronauts can’t do laundry in space—clothes are worn until they’re too dirty, then thrown out.

Aboard the ISS, astronauts communicate with mission control in Houston and Moscow. In space, your body fluids shift upward, giving astronauts “moon face.” Space boots have soles designed to grip onto handrails and footholds inside the station.

NASA has a “vomit comet”—a plane that flies in parabolic arcs to simulate zero gravity. Before spacewalks, astronauts pre-breathe pure oxygen to purge nitrogen from their bodies. Astronauts need to exercise at least two hours daily to fight muscle loss.

The ISS has had a continuous human presence since the year 2000. One astronaut brought a lightsaber replica to space to celebrate Star Wars. A career as an astronaut requires physical strength, mental resilience, and lots of patience.