Explore 11 Intriguing Facts About Life on the ISS

Sleeping in space is a unique endeavor. Astronauts must adapt to the challenges of zero-gravity slumber, spending considerable time acclimating to the unfamiliar environment. Despite the difficulties, they find solace in their specially designed sleep pods, where they spend an average of 6 hours per day in rest. These pods, equipped with insulation and ventilation systems, provide astronauts with a semblance of comfort amidst the vastness of space.

Astronauts aboard the ISS have a distinct perspective, gazing at the stars through small windows and dreaming of familiar comforts. While some may prefer the familiarity of Earth, the experience of sleeping in space is one they cherish for a lifetime.

When in space, you have to bring everything you need. That means astronauts need to be provided with food and water regularly alongside scientific equipment, experiments, and other essential needs. Launching supplies to the station is very costly, sometimes reaching tens or hundreds of thousands of USD per kg of mass. Hence, NASA and other space agencies will do whatever they can to limit the weight of cargo, ultimately reducing fuel costs.

An effective way to do this is by reducing the amount of water needed to be transported to the station. ISS achieves this by using a water recovery system that recycles urine from both humans and experimental animals, as well as condensation in the air and converts it into drinking water. It may not sound appetizing, but fundamentally, it's similar to what happens on Earth, just on a smaller scale.

So far, the water recovery rate on the station is about 93.5%, but scientists are aiming for 98%. Achieving that milestone will pave the way for missions to Mars in the future, where resupply will be more difficult, if not impossible. A new component of the recovery system was sent to the ISS in 2021 as part of this effort.

With the continuous advancement of science and technology, food on the ISS has been significantly improved compared to before. Alongside the journey into space, providing adequate nutrition for all astronauts throughout the spaceflight is highly prioritized. If you think astronauts would bring a bunch of rice, meat, oil, etc., into space for cooking, that's a crazy thought. In microgravity, astronauts cannot cook their own food.

All food items brought to the space station must be precooked, dehydrated, sterilized, and meticulously packaged in small pouches. Every few hundred grams of food brought to the ISS costs about 55 million dong, so all food items brought along must be as lightweight as possible. That doesn't mean astronauts on space stations always have to eat dry, bland things; in fact, sometimes they can still enjoy fresh foods. Occasionally, astronauts are treated to 'earthly' home-cooked meals like mashed potatoes or marshmallow candy thanks to NASA's regular food supply missions.

Living long in a special home beyond space, astronauts' taste buds gradually deteriorate, which is why spicy, flavorful foods are always preferred. Bringing meat onto the spacecraft is impossible, but dried beef is feasible because it's both lightweight and contains a lot of protein, especially its flavor is highly rated. Cereal mixed with milk is also one of astronauts' favorite dishes. Foods that need to be reheated by a microwave or undergo a process called 'rehydration' are edible. Instead of bread, astronauts have to use cornbread because it's compact, doesn't take up much space, and has a long shelf life of up to 18 months.

Spacewalking is a characteristic activity of astronauts and also one of the most dangerous activities. Spacewalks are conducted to repair, replace parts of the ISS, or to commemorate a significant event in the aerospace industry, such as the 40th anniversary of humans setting foot on the moon, for example. Each spacewalk can last for several hours.

When astronauts spacewalk, they have to wear a special protective suit, which is very large and bulky. This suit contains everything necessary for astronauts such as water, air, and other essential equipment. That's why this protective suit weighs over 100kg, but in such an environment, this weight is not a big issue. The outside temperature of the ISS is extremely harsh, reaching about 135°C during the day and dropping to around -135°C at night.

Have you ever wondered what would happen to astronauts without that protective suit? In the harsh conditions of outer space, because there is no air, lungs will collapse, and then the skin will be severely burned by solar radiation and other stars. So, each spacewalk places a tremendous responsibility on the shoulders of astronauts. As of now, humans have conducted nearly 200 spacewalks.

In reality, the distance from Earth to the moon is about 238,900 miles. The Apollo 11 astronauts took about three days to get there in 1969, but with the speed at which the space station is moving, it could go to the moon and back to Earth in just about a day. ISS isn't the fastest thing humans have ever built—that honor belongs to the Parker Solar Probe, which travels around the Sun and Venus at a speed of 430,000 miles per hour. However, the International Space Station orbits at an astonishing speed.

The station orbits Earth at a speed of about 17,500 miles per hour. At that speed, astronauts aboard the spacecraft circle Earth every 90 minutes, experiencing sunrise and sunset 16 times in every 24 hours. While astronauts and space travelers may not perceive it while working on the station, it means they're covering about five miles of space terrain every second. That's about 23 times the speed of sound.

Astronauts aboard the station can see a lot through the cupola, including large features, clearly visible. However, individual features can't be discerned from distances of 250 miles or more. Spotting the ISS spacecraft with the naked eye is much easier.

Space exploration often resembles a competition among different nations, but the International Space Station challenges that attitude. By definition, space is a realm without borders, representing an opportunity for the global community to work harmoniously rather than in opposition. When the station was first built, the United States and Russia were the only two partnering countries, but in recent years, there have been more countries and organizations joining in.

Today, the International Space Station has been constructed and crewed by NASA, Russia's Roscosmos, the Canadian Space Agency (CSA), the Japan Aerospace Exploration Agency (JAXA), and the European Space Agency (ESA), involving 11 countries. Space crew assignments on the ISS are allocated based on the relative contributions of each country or organization to the whole. To date, the station has hosted crews and visitors from 18 countries, including member states and some other countries. The station stands as a symbol of what can happen when humanity works together without borders and transcends political ideologies.

The theory of relativity tells us that the faster we move, the slower time passes for us. In our normal lives, we don't travel at speeds that significantly alter our subjective experience of time, but things are different when you move really fast. As we approach the speed of light, if we were to figure out how to do that, the subjective time change would make a real difference.

Despite its speed, the International Space Station still moves relatively slowly compared to the astonishing speed of 186,000 miles per second that light travels. However, the ISS is moving fast enough to measure the impact of time dilation on its inhabitants. An astronaut or space traveler spending a year on the space station would experience slightly less than one percent less time than us on the surface of Earth. It's not much, but it still means those in the station, compared to the rest of us, are time-traveling slower into the future.

ISS wouldn't be a suitable spacecraft without a robotic crew member. In an effort to realize our imaginations of space companions like Commander Data and the robot from 'Lost in Space,' scientists at NASA's Johnson Space Center (JSC) created Robonaut 2 as the first synthetic crew member of the station.

Often referred to as R2, evoking echoes of Luke Skywalker, Robonaut has been residing on the ISS since 2012. R2 features a visual system, sensors, and dexterous hands similar to human hands in terms of agility. The robot is capable of performing repetitive or hazardous tasks on behalf of the crew, freeing them up for important work or preventing them from encountering potential hazards.

However, Robonaut 2 is primarily utilized within the station as a testbed for future robotic activities in long-duration space missions. What the crew learns about Robonaut's capabilities could lead to more advanced robots assisting astronauts in missions to Mars.

At any given time, the space station typically hosts a crew of seven on the ISS. There are occasions, especially during crew changeovers, when there may be up to 13 crew members temporarily aboard, but those instances are rare and short-lived. Because the station has continuously been inhabited for over two decades, there's been a significant turnover. As of February 2022, 251 individuals have visited the station, hailing from 19 different countries.

As mentioned earlier, crew assignments primarily depend on a nation's contribution to the program. Therefore, the majority of the station's crew, 155 astronauts, come from the United States. Another 52 are cosmonauts from Russia, 11 are astronauts from Japan, 8 are Canadian astronauts, including Chris Hadfield, who commanded the station, and 5 come from various European Space Agency member states or visiting nations. Currently, the record for the most visits to the station is held jointly by Yuri Malenchenko and Fyodor Yurchikhin, both having been to the ISS 5 times.

President Reagan signed off on creating the space station in January 1984 with the goal of becoming operational within 10 years. While that timeline ultimately wasn't met, the station was finally constructed. The first segment, the Zarya control module, was launched by Roscosmos in November 1998 and was met in orbit by NASA's Unity module just two weeks later. Additional modules and supply deliveries were completed over the ensuing decade before the station was finished.

In total, over 30 missions were necessary to deliver modules, conduct repairs, and stock the station. Many of these missions were carried out using various space shuttles – in fact, that's why the shuttle program lasted as long as it did. Construction of the station was completed in 2009, after which it became fully operational, coinciding with the 10-year anniversary of its continuous habitation.

The International Space Station is the largest spacecraft ever built with quite an extensive span. If we were to place it on the ground, the ISS would stretch across an entire football field from end to end. With a length of 357 feet and a weight close to 1 million pounds, the station offers ample space for the crew to move around and accomplish their objectives. With the expanded BEAM module, the ISS boasts a massive interior space measuring 32,898 cubic feet - though much of the area is used for equipment storage. Nonetheless, there are plenty of amenities for the crew.

The station has sleeping quarters, bathrooms, and a gym where astronauts spend two hours each day to prevent bone and muscle loss. However, its best feature is the cupola that allows astronauts to gaze out the window at Earth below. The ISS station is so large, so the station may soon be built even larger. Plans are in place to add three additional modules to the station in the coming years, potentially bringing us one step closer to a city of a thousand planets.