After 17 years in orbit, how durable is the International Space Station?

FILE- In this April 20, 2014, image made from a frame grabbed from NASA-TV, the SpaceX Dragon resupply capsule begins the process of being berthed on to the ISS.(AP Photo/NASA-TV, File)

Even though the ammonia leak that forced a partial evacuation of the International Space Stations U.S. section on Wednesday proved to be a false alarm, the news did raise questions on the stations durability.

Since the stations inception in 1998, the habitable satellite has endured a multitude of maintenance issues, from pump failures to damaged panels. Weve had other, what have turned out to be more serious, problems on the space station, NASA spokeswoman Stephanie Schierholz told FoxNews.com. For example, there was an actual ammonia pump failure [in 2010], and so it had to be replaced and required space walks. The actions we took [Wednesday] were for a worst-case scenario like that.

The now 17 year-old International Space Station (ISS) has been occupied for 5,187 days and circled the Earth 92,357 times, so a little wear-and-tear would seem unavoidable. While the station has been in orbit since 1998, it actually wasnt completed until recently.

The first piece of the space station was put in orbit [in 1998], but the assembly actually took quite a bit of time, and wasnt completed until 2011, Schierholz said. We were using the space shuttle to complete the building of the ISS, because we would bring pieces of the station up in the space shuttle, so every time we brought up a new piece itd change the configuration. So the building of the space station took quite a bit of time.

The road to the stations assembly saw more than its fair share of bumps along the way. Following the space shuttle Columbia disaster in 2003, there was a two-and-a-half year suspension of the U.S. shuttle program, leading to a large waste accumulation aboard the ISS that held up operations in 2004. A computer failure in 2007 left the station temporarily without thrusters and oxygen generation, followed by a torn solar panel that same year which required astronaut Scott Parazynski to make a daring impromptu spacewalk on the end of the space shuttles OBSS inspection arm. In 2010 there was the aforementioned ammonia pump failure, which, according to Schierholz, would be the top [maintenance issue that has come up] from an unexpected work/volume of work-required [standpoint]. The interesting thing about all these [problems] is that theyre anticipated failures -- we train the astronauts for them. We do plan space walks to replace parts that we expect or are at the end of their life cycle. This failed sooner than we expected it to.

The following year saw the station almost collide with what is becoming a rapidly rising threat: orbital debris. With more and more dead satellites in orbit, the possibility of one of them hitting the ISS is a growing one. These satellites sometimes slam into one another, the ensuing blast creating thousands of pieces of orbital debris.

They are an issue, Schierholz said, because if something were to hit the space station - the ISS is traveling at 17,500 mph, a piece of debris could be travelling at the same speed, and theres going to be some damage thats caused as a result of that. The U.S. Air Force tracks any piece of debris thats bigger than a golf ball, and theres a certain amount of protection from micrometeroid debris, which is natural stuff in the universe that is too small to cause any real problems. But any debris that was put there as a result of an accident is a concern to us, especially because we have people on board. To avoid disaster, thrusters are fired to adjust the stations orbit out of harms way.

So after 17 years of dodging space junk and enduring technical problems, the question remains: how much longer can the ISS stay operational? According to NASA, for as long as the U.S. and its international partners pay to maintain it.

The space station is certified for a particular lifetime, Schierholz said. So thats how we assess the future lifespan of the space station."

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After 17 years in orbit, how durable is the International Space Station?