Most of us are pretty familiar with the International Space Station these days, and the fact that, if you want to get there, it's as simple as blasting off in the Russian Soyuz rocket, docking with the ISS, and then popping open the hatch and high-fiving all your astronaut friends. Astronauts are making these trips all the time now, so it's got to be pretty easy, right?

Actually, no. As the latest episode of Smarter Every Day above explains, despite how common visits to the ISS have become, the journey is actually way more complicated than that, and it involves a lot of orbital mechanics and physics. In fact, you could say, it's rocket science. But Destin manages to explain it so well, even I can understand it.

To find out exactly what's involved in flying a spaceship to the ISS, Destin meets up with veteran astronaut Scott Kelly, who's about to embark upon a record year-long trip to the space station, in order to find out more about the effects of long space travel on humans. Meanwhile, Scott's twin, Mark, will be staying on Earth so that NASA can see how Scott's body changes over the year - which is all part of their continuing research on sending humans to Mars.

Not only is it fascinating to be able to chat to an astronaut inside the Soyuz capsule just a few days before he takes off on a species-first journey, it also provides us with some incredible insight into how exactly the Soyuz is controlled.

Our favourite part? The fact that astronauts control the rocket using a stick.

So what do they do with that stick that enables them to dock with a space station travelling almost 30,000 km (17,500 miles) an hour, 400 km (250 miles) above Earth? Well this is where things get kind of tricky. After the Soyuz blasts off, it takes 9 minutes to get into space. And from there, the boosters cut out and the astronauts are pretty much floating (or falling) in orbit around Earth. 

From here, they need to do a series of burns to expand their orbit slightly, and correct themselves so that, while they're travelling slower than the ISS (around 27,000 km, or 17,000 miles, per hour), it takes them the same amount of time to travel around Earth because their orbit is smaller. Then it's just a case of waiting until the right moment and whizzing around the planet in sync with the ISS, before another set of burns position them directly in front of the space station.

So how do they actually dock? Well, that involves a pretty high-tech, space U-turn. And we'll let Destin explain how that works because, after all, this is rocket science. But he does such a good job that I actually understand it. My mum would be so proud.