國際太空站25週年：太空站的秘密和驚人的數據揭曉！

The International Space Station, known as the ISS, has been orbiting Earth for 25 years and is considered one of humanity's greatest engineering achievements. Floating about 400 kilometers above our planet, the ISS is a symbol of international cooperation, with astronauts from many countries living and working together in space. Since the first crew arrived in November 2000, more than 280 astronauts and cosmonauts have visited the station, and it has been continuously occupied ever since. For anyone born after November 2, 2000, there has always been someone living in space.

The ISS began with the launch of its first module, Zarya, from Kazakhstan in 1998. At first, the station was just three small modules connected together, and the first crew—Bill Shepherd, Sergei Krikalev, and Yuri Gidzenko—spent almost five months in these cramped quarters. They conducted scientific experiments, performed spacewalks, and welcomed visiting Space Shuttle crews. Over the years, the ISS has grown to include many more modules, solar arrays, and complex systems. Today, the station is about the size of a six-bedroom house, but in microgravity, astronauts can use every surface, including the walls and ceiling.

Life on the ISS is unique and challenging. Astronauts must exercise for two hours each day to prevent their muscles and bones from weakening due to weightlessness. The station has a gym with a treadmill, cycle, and resistance machines. Water is precious in space, so the ISS has a recycling system that turns sweat, breath, and urine into clean drinking water. The air is constantly filtered, but the station is not completely free of germs. Astronauts spend much of their time conducting experiments, and more than 4,400 research papers have been published based on ISS science.

The ISS has hosted astronauts of all ages, including Don Pettit, who was 70 when he lived on the station. The longest single mission on the ISS lasted 371 days. Sleeping in space is different, as astronauts use special sleeping bags attached to the wall to keep from floating away. There are four toilets on the station, and fixing them is a big job.

Food on the ISS has improved over the years. Astronauts have baked cookies and enjoyed pizza nights. Some have brought musical instruments, like guitars and flutes, and even played didgeridoos. The Cupola, a large window on the station, offers stunning views of Earth, and astronauts often take photos to share with people back home.

The ISS travels at 28,000 kilometers per hour, so astronauts see 16 sunrises and sunsets every day. The station sometimes has to move to avoid space junk, which can damage its structure. Canada's contribution to the ISS includes the Canadarm2, a robotic arm used for assembly and repairs.

Space travel is expensive. Visiting the ISS as a private tourist costs about $55 million for a seat on a SpaceX rocket. The station is powered by huge solar arrays and contains more than 486,000 items, each tracked with a barcode.

The ISS has cost around $150 billion to build and operate. It stands as a testament to what people can achieve when they work together, helping us learn about science, technology, and life beyond Earth. The ISS continues to inspire new generations to explore and discover.