Look up at the sky on a clear evening and you might see a bright dot moving quickly between the stars, without blinking. It is not a plane. It is the International Space Station, the largest object that humans have ever built in space.
The station, often called the ISS, orbits the Earth about 400 kilometers above our heads. It moves at about 28,000 kilometers per hour, so it goes around the planet in roughly 90 minutes. This means that the astronauts on board see about sixteen sunrises every day.
The ISS was built piece by piece, starting in 1998, by space agencies from the United States, Russia, Europe, Japan and Canada. People have lived on it without a break since the year 2000, and each astronaut usually stays for around six months.
Life without gravity is strange. Astronauts sleep in sleeping bags tied to the wall, so they do not float around. Water forms round balls in the air, so they drink from bags with straws. In space, muscles and bones become weak, so the crew must exercise for about two hours every day.
Most importantly, the ISS is a laboratory. Scientists use it to study how plants, animals and the human body behave in space. In 2022, Eytan Stibbe became the second Israeli in space when he spent more than two weeks on the station, carrying out experiments by Israeli scientists.