Astronauts follow strict schedules to mimic Earth days and stay healthy in space

Emulating Earth’s light-dark cycle is important for astronaut health and safety

Astronauts aboard the International Space Station experience 16 daily sunrises, but scientists have learned to try to promote circadian rhythms by phasing through several light settings aboard the ISS to improve astronauts’ sleep and productivity.

Astronauts exercise on the International Space Station

Astronauts maintain bone, muscle, and cardiovascular health with physical activity. It's crucial astronauts make time to exercise for approximately two hours per day. This resource offers a behind-the-scenes look at how high-intensity workouts help prevent muscle atrophy, bone density loss, and aerobic decline during months-long space missions.

Watch what it’s like to spend a day on the International Space Station

Microgravity makes personal care more complex on the International Space Station, where stray, floating materials must be captured to prevent them from entering vents and clogging filtration vents. No-rinse shampoo, water pouches, and other strategies help minimize obstructions.

Watch how dozens of everyday human tasks are performed in space

This playlist features clips of astronauts aboard the International Space Station explaining how they cook, eat, sleep, and conduct research in microgravity. Other activities to pass the time, including watering plants and playing soccer, are also shown.

Research suggests the cleanliness of the ISS may make astronauts unhealthy

The International Space Station's sterile conditions deprive astronauts of the opportunity to strengthen their immune systems through microbial exposure. To address this problem, future missions may use probiotic-based cleaners and foster diverse microbes in space habitats.

How do astronauts battle loneliness and depression?

You’re stranded hundreds of miles away from your friends and family, constantly surrounded by coworkers who also are your roommates, and you’re only allowed the shortest of walks outside. There’s also no takeout, and gravity has essentially broken up with you. You might need a little help adjusting mentally. That’s where space psychologists and psychiatrists step in, according to this article.

Civilians on short-term spaceflights can experience long-term astronaut health impacts

A collection of 44 studies—primarily based on data from a 2021 tourist trip to low Earth orbit—identified immune system disruption and some kidney damage in tourists, with women appearing to recover from space travel faster than men. Return trips from Mars may require human travelers to be on dialysis.

Protecting astronauts against space radiation

Outside the protective atmosphere of Earth, astronauts are constantly bombarded by radiation, which, among other dangers, increases the risk cancer. While those of us on Earth can mitigate the effects of similar radiation by limiting exposure,...

Drugs in space: the pharmacy orbiting the Earth

Researchers are developing pharmaceutical solutions for astronauts, whose bodies may not respond the same way in space as they would on Earth. Similar to how microgravity causes changes to astronaut physiology, the environmental shift enables new...

Studies suggest when you sleep is as important as how much you get

"Molecular clocks" made of timekeeping proteins and genes help regulate the body and its processes, meaning the disruption of one cog will impact another. Those who live in sync with their circadian rhythms report less fatigue, clearer thoughts, greater medication benefits, and better long-term health outcomes.

We don't know why astronauts get motion sick

Between 60% and 90% of astronauts get motion sick in space—and many also get motion sick during the first few days upon return. Motion sickness on Earth does not seem to correlate with whether or not astronauts get motion sick in space, so it's not possible to predict who will get ill.

Studies suggest when you sleep is as important as how much you get, and syncing with your circadian rhythms may lead to less fatigue and improved long-term health outcomes

The crew of the ISS creates unique memorials for deceased colleagues

The continued human occupancy of the International Space Station since 2000 has led to the development of social and cultural elements by crew members, which the ISS Archaeology Project has catalogued. Records of handmade cakes, decorations, and memorabilia highlight the human aspect of living in space.

Watch a montage of space-based Earth views as astronauts discuss their overview experiences

As of 2023, more than 600 astronauts and 63 space tourists have seen Earth from space, experiencing a life-changing perspective shift as they view the entirety of our home planet.

A look at the foods eaten by astronauts during and after the space race

After John Glenn became the first American to demonstrate that eating in space was possible by eating apple puree out of a tube, meals were prepared for astronauts to meet an approximately 2,800-calorie-a-day requirement via freeze-dried foods. Meal quality gradually improved throughout the Apollo program, including the Apollo 8 crew's nondehydrated Christmas meal in 1968.

Explore a timeline of the International Space Station National Lab

In 1984, President Ronald Reagan called for establishing a human presence in space, which began with NASA astronaut Bill Shepherd and Russian cosmonauts Yuri Gidzenko and Sergei Krikalev on November 2, 2000. Humans have continuously occupied the ISS every day since.

Olympians view sleep as a performance tool, prioritizing routine and environment

Elite athletes emphasize consistent sleep routines, dark and cool environments, the well-placed nap, and tools like eye masks, white noise machines, and supplements like melatonin (particularly for jet lag). This priority belies a core principle: recovery and performance are inseparable. Read more ways Olympians "sleepmaxx" here.

It is impossible for astronauts to burp in space

Due to Earth's gravity, liquids and solids sink in our digestive system, while gases rise, allowing them to be forced back up the esophagus to be expelled through burping. In the microgravity environment of the International Space Station, burping would result in vomiting if it were possible.

The International Space Station is slowly falling due to atmospheric drag

To stay in orbit, the largest human-made object in space needs periodic rocket boosts to maintain its orbital speed and height. Its solar panels collect enough energy to power over 60 average US homes each year.

NASA uses extreme Earth environments to prepare for space exploration

Analog missions in volcanic terrains and craters mimic Martian and lunar environments. Crew members operating in these missions, including at sites in Utah, Nevada, Arizona, and Hawai'i, test suits and specialized space instruments under simulated conditions.

A 'holoported' medical team has been beamed into the International Space Station

In 2021, using the Microsoft HoloLens Kinect camera and custom Aexa Aerospace software, NASA's flight surgeon led a team of hologram doctors on a pioneering visit to the space station, marking a significant advancement in communication and telemedicine technologies that will be crucial for future deep-space missions.

Social jetlag—differing weekend and weekday schedules—is physiologically similar to jet lag

Recovering from schedules that drastically differ between weekends and weekdays, something that was first described in academic work in 2006, is a growing concern in public health as more research shows that consistent daily routines are important for human health.

View the docket of future SpaceX launches

SpaceX has established an efficient schedule for launches of ISS crew shuttles and Starlink satellites, with blastoffs occurring just under once every four days in 2023—a pace that has since accelerated as the company has won more contracts.

Astronauts have repaired genetic damage in space using CRISPR—a molecular tool that can make precise changes to DNA and is used in single-celled organisms to attack invasive viruses.

Orbital spaceflight requires reaching 23 times the speed of sound

After the spacecraft accelerates up to at least 17,500 miles per hour, space tourists can travel in elliptical orbits hundreds of miles above Earth for days or weeks at a time. Suborbital flights instead max out at about 2,200 miles per hour and travel only 50 to 70 miles above Earth's surface for a few minutes.

The Polaris Dawn was a privately crewed spaceflight

SpaceX's Crew Dragon capsule Resilience spent five days in low Earth orbit as part of the first of three planned missions under the name Polaris Dawn. The historic journey took participants farther away from our planet than anyone has been since the Apollo missions.

Where did the term ‘astronaut’ come from?

Astronaut essentially translates to space sailor, though these sailors may be referred to differently depending on their home country. For example, Russian star sailors are called cosmonauts. Though why American, European, Canadian, and Japanese...

Before humans, the Soviet Union and the United States sent animals—including apes, dogs, and cats—to space during the Space Race.

Researchers believe the brain consolidates memories, processes emotions, and plans for the future during dream states

While the sun's gravity keeps the planets in orbit, their gravity also pulls on the sun, causing it and everything else in the solar system to orbit around a mutual balance point called the barycenter—the true center of the solar system.

Stars appear to twinkle because turbulence in the motion of molecules in Earth's atmosphere causes light to bend and wiggle rapidly on its way to the surface—a phenomenon called scintillation.

Explore our favorite visualization of the immense scale of space, from an astronaut to the size of the observable universe

SpaceX's S-1 or 'prospectus' revealed many previously unknown details about the company, including its unprofitability despite doing $18.7B in revenue in 2025, exactly how many voting shares Elon Musk will have in the company (roughly 85%), and more.

Learn how your body is, scientifically, like a firework with its own slow, controlled burn.

Children are now three times more likely to say they want to be a YouTuber when they grow up than an astronaut, with some even attending 'YouTube camps' that teach kids how to create content for the platform.

After 25 people used virtual reality headsets to practice flying with virtual wings—flapping their arms—their visual cortex responded to the wings almost as if they were real arms, treating them as body parts.

About 12.5% of US adults experience a phobia in their lifetime, a diagnosis that hinges on the intense fear interfering with daily life and persisting for at least six months.

Take a 3D tour of the Hajj, Islam's annual pilgrimage to Mecca, undertaken by over 1.5 million Muslims.

Watch the cumbersome, but necessary, precautions healthcare workers must take to care for and protect themselves while caring for Ebola patients.

This real-time tracking of the hantavirus cruise ship outbreak in May 2026 offers a unique glimpse into the global reach of the outbreak and whether the virus sickened passengers and their communities around the world.

Sunflowers have long been a symbol of nuclear disarmament because they can extract large amounts of radioactive cesium from soil.

NBA superstar Victor Wembanyama spent the 2025 summer training with monks in central China to enhance his body and mind.

A 2019 Facebook event called on attendees to "Storm Area 51, They Can't Stop All of Us," resulting in countless memes, the creation of a music festival, and eventually the arrests of those who did try to approach the area.

Coral polyps reproduce via broadcast spawning, where entire reefs simultaneously release reproductive cells for about one hour, once a year.

SpongeBob exemplifies Aristotle's philosophy for living well because he understands that happiness doesn't come from external factors like money, recognition, or power.

Massive 3D printers have been used to build homes by stacking layers of 'concrete toothpaste,' a fire-resistant material that effectively insulates against outside noise.

After the Boston Tea Party, colonists switched to coffee, which became the main morning drink for revolutionaries.

In 2026, Finland was named the world's happiest country for the ninth consecutive year based on its wealth, social safety network, and high life expectancy, among other factors.

The distributor behind 'Rocky Horror' pulled the film from its scheduled national release, believing it would be a failure, though it eventually amassed a dedicated fanbase through midnight showings, a trend that continues over 50 years later.

Hotels in Cannes, the glamorous city on the French Riviera, hire hawks to ward off seagulls during the city's famous film festival.