 The sweet smell of life support, presented by Science at NASA. When NASA astronaut Shell Lindgren blasted off from Kazakhstan in July of 2015 for his first expedition aboard the International Space Station, he had some lofty expectations. I was eager to see Earth from space, and I couldn't wait to float in microgravity. And he confessed. I kind of expected the International Space Station to smell like a locker room. After all, what would you expect? It's an airtight spaceship continuously occupied 24-7, 365 days a year, by as many as half a dozen hard-working and exercising astronauts. Lindgren was in for a surprise, however. The air in the space station actually smelled great. The filters and the life support system do a great job cleaning the air. There were no issues at all. First contact with the space station's clean air reminded Lindgren a flight surgeon of the impressive technology underlying the station's life support system. On the International Space Station, we're testing technologies that will allow us to live comfortably during long journeys into the solar system. Our life support systems provide a properly pressurized atmosphere with the right amount of oxygen. It scrubs carbon dioxide from the air. It keeps the temperature in a comfortable range and provides fresh water and light and everything that we need for good hygiene. Hence the sweet smell of the air. While I was on the International Space Station, I felt a lot like a bridge builder, helping to pave humanity's path to Mars. As mission planners look toward the Red Planet, we are definitely evolving from the lessons learned on ISS, says Molly Anderson, a principal technologist at NASA. We want to increase the level of recycling wastes beyond what we do on the station now. Our ISS water system can recycle about 93% of the wastewater back to clean water. The leftover fluid is referred to as brine, and we're flying a demonstration technology on station soon that will recover most of that water too. On the station, if all the systems are working, we can recycle a little less than 50% of the carbon dioxide back into oxygen. We're trying to get that number much higher to at least 75% and even up near 100% she continues. While the space station still relies on cargo vessels to bring fresh supplies and equipment, improved life support systems can help reduce those needs, leaving more room for science and science equipment going to the station. Plus, Earth won't be able to help on missions that leave Earth orbit. Hundreds of millions of miles from Earth, no one will be able to bring us fresh water or replace malfunctioning systems. We will be on our own, just us and the life support system. That's why it is crucial for life support development to proceed aboard the station, an excellent test bed for future deep spaceflight. For more from the International Space Station, go to www.nasa.gov. For more news about the sweet smell of spaceships and the systems that support them, stay tuned to science.nasa.gov.