The International Space Station turns 20 years old

When the hatch of the International Space Station was first opened twenty years ago, the well-known smell of space was probably not yet very present. That must be different by now; the ISS turned 20 on Monday, and after visits from dozens or even hundreds of astronauts, the space station is starting to run out of technological space. And it is not yet known how long it will last.

On Monday, November 2, we celebrate the ‘birthday’ of the International Space Station, but you could actually celebrate that date a little earlier. Already on November 20, 1998, the first module of the station was launched into space. Zarya is a Russian module and one of the most important for the station, at least in the early years. The station now consists of dozens of such modules, but also coupling gates, solar panels and other components.

On Monday, however, we celebrate a more symbolic birthday. On November 2, 2000, exactly twenty years ago, a crew of two Russian cosmonauts and an American astronaut arrived at the station. Not a day has gone by since then that there wasn’t at least one astronaut in space. They work and live there, in recent years even for months at a time. Since that first flight by Bill Sheperd, Yuri Gidzenko and Sergey Krikalev, 241 astronauts have visited the space station, conducted spacewalks and docked commercial spaceships, and the participating countries managed to largely ignore international tensions on earth. But now the ISS is also starting to show cracks. Literally, because a large hole was recently discovered in the space station, and the countries are increasingly talking about a future that may take place without each other.

Numbers

First, let’s take a look at the performance of the drive. A total of 241 astronauts and cosmonauts flew to the space station, spread over 19 countries. Since December 1998, 230 spacewalks have been conducted to assemble and repair the station. A total of 42 flights were performed to bring all parts of the station together, 37 of which were performed aboard the Space Shuttle. The remaining five were carried out by Russian Proton and Soyuz missiles. After all, the Space Shuttle had much more cargo space than the Russian rockets, which meant that a much larger space station could be built than originally intended.

In total, about 350,000 sensors keep track of how the station and the crew are doing. In the American part of the space station, this information is collected via a hundred different networks. To control this, code of more than 1.5 million lines is used. That is only for the flight software. The software Houston mission control uses has more than three million lines of code. Since last year, this information has been sent to earth at a speed of 600Mbit/s .

Astronauts use their time aboard the station primarily to conduct scientific experiments. It involves more than 3000 tests on microgravity, which sometimes go on for years. In addition to those experiments that the crew performs, the space station contains twenty measuring instruments that are located on the outside of the station.

The experiments

It is with those experiments that it becomes a lot more difficult to justify the importance, and also the enormous costs, of the space station. Because what actually happens in the ISS sometimes remains somewhat vague, and whether it justifies the price tag of about 150 billion euros.

Astronauts themselves you hardly hear about the work they do. “We are just performers”, André Kuipers said in an interview years ago . “All kinds of scientists come to you in advance and tell you what needs to be done, what exactly you need to measure and test, but just as often you don’t know exactly how a research project works.”

In total, more than 1800 scientific papers have resulted from research at the ISS. NASA itself keeps lists of scientific achievements from the space station, including some medical discoveries such as understanding how Duchenne’s disease works . But a great deal of research also seems to be carried out specifically in space simply because it takes place in space. For example, experiments are being carried out with 3D printing in weightlessness and maintaining plants in space , which may be useful in the future if we want to live on planets.

A great deal of research is also being done into the effects of weightlessness on the body. A well-known example is the breakdown of bone and muscle mass, which is much studied . That information is also useful for doctors on Earth who conduct research on that subject, but whether that necessarily requires a stay in space is another matter.

Another well-known example that was in the news a lot is the mission that lasted almost a year . That was not, as is often thought, only a mission of the American Scott Kelly, but also of the Russian Mikhail Kornienko. The pair spent 340 days on the space station, taking a close look at the effect of such a long stay on the body. In addition, Kelly’s mission was particularly interesting. His twin brother Mark was also an astronaut and went through the same medical tests on Earth as his brother did on the ISS. In that Twin Study the difference between the two was studied. Although differences were indeed found in, for example, the gene composition of the spaceman, the conclusion turned out to be mainly that the differenceswere not very significant . It was already known that people can stay in space for a long time without major complaints, and Kelly and Kornienko also did not break a record. Valeri Polyakov once spent 437 days on the Russian space station .