Mark Vande Hei and Tom Marshburn will spend this Christmas further away from home than any other beings in the universe.
The two astronauts are orbiting the planet on the International Space Station. Marshburn says he and Vande Hei likely plan to work through Christmas – but not without a video call home to celebrate with their families.
Ideally, the duo would take Christmas off. But while the rest of us on Earth have been holiday shopping and planning celebrations around the pandemic, the astronauts have been working on a cargo vehicle that's not yet finished, Vande Hei says.
On his last space flight, Vande Hei and his American colleagues worked hard on Christmas Day. The Russian astronauts, however, spent the holiday decorating their part of the space station and invited the Americans over for dinner, he says.
"We were very pleasantly surprised that they had a nice spread for us," Vande Hei says. "So it’s fun to be up here with wonderful people."
Fellow astronauts from Russia, Japan and Europe co-inhabit the ISS. Beyond the holidays, Vande Hei says all of the astronauts share a sense of international camaraderie on the space station.
For Vande Hei, training with astronauts from around the world and learning about different cultures and languages is one of the best parts of working on the space station.
"It’s a very eye-opening experience," he says. "And the space station is really supporting all of humanity so it gives us a very good sense of purpose."
To celebrate the holiday back in 2012, the astronauts had a tiny decorated Christmas tree on the space station. Marshburn recalls that he and the other astronauts back then could attach the teeny foot-and-a-half tree on the ceiling or wall — but he would need to check the station database to see if it's still on board.
This year, Marshburn says they hope to hang some stockings — not the simple cloth ones used here on Earth — and dress up in Santa hats to indulge in the festive spirit.
And don't worry kids, the astronauts are hopeful Santa Claus will find a way to get through the airlock and deliver presents to the good boys and girls working on the station.
Astronauts have a tough job: Vande Hei and Marshburn recently took shelter in a spacecraft when satellite debris threatened to crash into the space station. And they dealt with an ammonia leak earlier this year.
That might sound stressful, but it's exactly what astronauts train for.
"I think we’re so well trained that we get simulations where everything goes wrong," Vande Hei says. "So when we have something that goes wrong and it’s not the full complement of wrongness, it feels like it’s an easy simulation."
When simulations go awry on the ground, the ground control team isn't there to help — so having that support makes these real situations seem easier than the training and adventurous, he says.
For Marshburn, the satellite debris risk felt like an easy simulation. The astronauts calmly boarded the vehicle and closed the hatch, which they can't do in simulations on the ground, he says.
"We had some food and water with us and we just waited it out and didn’t have any concerns. If we needed to, we knew that we could just depart the space station, " he says, "but [I'm] glad it all worked out and we could stay on board."
Marshburn first went up to the space station in 2009 and he's staying on for the 67th expedition when this rotation ends. He starts to miss certain of living beyond our world over time like zero gravity, the view of the Earth and working with people from around the world.
"It’s an incredible international endeavor. It was something I was very proud to be a part of," he says. "When I left the space station, I talked to my family. They said they were OK with me coming back. And so then I just began making preparations to come back again, if I could."
On this expedition, the astronauts' bodies are holding up so far. To work out in space, Vande Hei says they use a "resistive exercise device that uses vacuum cylinders instead of weight," a treadmill that requires strapping down with bungee cords to run on the wall and an exercise bike that's currently missing its seat.
"It looks kind of funny," Vande Hei says, "if you’re used to being one orientation and you see someone running with their head off to the side."
When Marshburn looks out the space station window, he can see clouds, a sunset and a lot of blue. This time of year, the space station is in orbit along what's called the terminator, the line that separates day and night, so the astronauts often feel like they're in the middle of a sunrise or sunset.
"Especially when I first got here, I looked outside, I had no idea where I was," Marshburn says. "It wasn’t like looking at pictures in an atlas."
As humanity turns the page on 2021 and starts a new year, Vande Hei says he hopes that humans approach the COVID-19 pandemic with a "strong sense of unity."
When it comes to the climate crisis, he hopes people realize the impact that Earth's thin atmosphere — essential to our existence, where most humans spend their entire lives — is a finite resource that needs protection.
"I think the Earth is going to be around for a long time," he says. "Whether or not we are, it’s really up to us."
This article was originally published on WBUR.org.
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