Astronaut Couple Doing Back-to-Back SpaceX Missions Reveal Details About Life on Space Station

Before Megan McArthur puts on her custom space suit next Thursday and straps into the same Crew Dragon capsule seat that her husband, Bob Behnken, rode to the International Space Station (ISS) last summer, she plans on taking a really long shower.

"They'll probably have to yell at me to get out of it," she tells PEOPLE.

It will be her last one for six months. The good news is that one of the activities that she and Behnken like to do with their 7-year-old son, Theo, is camp, which is what living on the ISS is like. Instead of showers, astronauts take sponge baths, and hair washing is done with no-rinse shampoo. But while Behnken spent two months on the ISS last summer, McArthur, 49, will be up there for six months.

"There are a lot of kind of mundane tasks that you need to figure out how to master in zero gravity, whether it's clipping your toenails or getting clean," says Behnken, 50, who has spent more than 93 days in space over his three missions. "But to make up for having to relearn how to do all those more mundane tasks, there's some pretty exciting things that you can do as well, like looking out the cupola on the bottom."

"I think every astronaut cherishes the opportunity to just spend a full day-night cycle looking out the window and watching the Earth go through sunrise and sunset, and watch lightning storms," he adds.

There are some emotional tasks to overcome, too, like leaving your son for six months, as friend and colleague Karen Nyberg did when she spent six months on the ISS in 2013 when her son, Jack, was 3.

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William J. Stafford/NASA Megan McArthur and Bob Behnken

"It's hard for a mother to leave her child for that long a time," says the now-retired Nyberg, who had a heart-to-heart with McArthur about it. "You just need to hear those few words: 'Yeah, it's hard, but in the end, it's going to be okay. Your kid is going to be proud of you, and your life goals matter, too.' All those sorts of things because you can really doubt that you made the right decision. I know I did at times."

The good news is that McArthur can phone home pretty much anytime (she's looking forward to surprising her mom with a call from space), and there will be weekly video chats with Behnken and Theo, who can also tune into NASA TV to see what his mom is up to on a regular basis. Mostly, she'll be conducting all kinds of different experiments, from how fire moves around in zero gravity to how the human body withstands it for long space missions. She'll also be exercising two hours every day to keep bone loss from occurring, which can happen in weightlessness and lead to serious complications down the road.

William J Stafford/NASA Megan McArthur and Bob Behnken with son Theo

The living and working space inside the ISS is about the size of a six-bedroom, two-bath house with a gym and a big bay window that offers a 360-degree view of Earth. Each astronaut sleeps in a sleeping bag inside a large locker, which they can float around in or be more restrained if they like.

But the best part might just be pretending to be Superman—or Superwoman.

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Courtesy Megan McArthur and Bob Behnken Megan McArthur and Bob Behnken with son Theo

Says Behnken: "Getting a chance to fly as a human without a spaceship is a pretty cool experience, to see if you can fly from one end of the space station to the other without bumping into anything. Theo would enjoy that."

If you'd like to see the ISS fly overhead, click here to sign up for NASA alerts. As the third brightest object in the night sky, it's easy to find if you know when and where to look.