Scott Kelly can see the finish line for his #YearInSpace. The 52-year-old NASA astronaut has only got about a week left aboard the International Space Station until he’s finally back home on Earth. But before we all start throwing out high-fives under a giant “Mission Accomplished” banner, it’s important to remember one thing: The mission isn’t over.

Although Kelly and fellow Russian cosmonaut Mikhail Kornienko will have spent a year in space (well, technically 340 days, but let’s not play semantics here), the science of their mission will altogether span more than three years, according to NASA.

See, before Kelly and Kornienko jetted toward the ISS so that we could study the effects long term space duration had on the human body, the pair had already spent a year being observed and studied by physiologists on the ground. Their blood, urine, saliva, and other bodily fluids and tissues were sampled and analyzed every which way you could imagine. They were run through a slew of tests designed to measure their biology. In short, they were like guinea pigs — only trained to spacewalk.

When the two get back on the ground, they’ll be resampled in every which way, and run through another several dozen tests. All of that data will take more than a year to fully analyze.

What’s more, it won’t just be NASA’s scientists who have the opportunity to parse through Kelly’s data. Researchers from around the world are expecting to take part in many different types of related investigations, and they’ll all need access to the data in some form or another. Some bodily fluid samples from Kelly and Kornienko will actually be stored on the ISS and not returned until the next SpaceX Dragon spacecraft can complete its ISS resupply mission.

Astronauts Mark and Scott Kelly

Kelly’s role in all this is actually very unique in the context of his twin brother, Mark (a retired astronaut himself). The two are part of twin studies that are further investigating the physiological effects of long term space duration by using Mark as a control subject. This is crucial when it comes to understanding the underlying genetics that could affect someone’s ability to undertake space exploration.

All in all, the fun doesn’t stop once Kelly finally touches down back on Earth. Fun for us at least — giving your urine up to sample isn’t quite the same as gazing on the blue planet from above.

Photos via NASA