Video screenshot by Bonnie Burton/CNET

Don't panic! Even though fans already celebrated Towel Day on Monday, you can still honor the late, great sci-fi author Douglas Adams by watching astronaut Samantha Cristoforetti as she reads about towels from the author's book "A Hitchhiker's Guide to the Galaxy," while she's floating upside down in space!

Towel Day was first held on May 25, two weeks after Adams died in 2001. Every May 25 since then, fans of his work carry around a white towel, which refers to its mention in "A Hitchhiker's Guide to the Galaxy."

"A towel, it says, is about the most massively useful thing an interstellar hitchhiker can have," according to the book.

In addition to reading about towels from Adams' book, Cristoforetti also tweeted photos of herself wringing towels while stationed on ISS in honor of Towel Day.

This is no surprise to both geeks and fans of Cristoforetti, since the European Space Agency astronaut also wore a in space and, of course, took a selfie in it!

As the first Italian woman in space, Cristoforetti is a groundbreaker herself, but we're just excited to see her show off her love for all things geeky while she's on the job above us. She's in good company.

Lately, astronauts have been showing off their nerdy passions. We've seen them dressed up as Jedi Masters, sing a cover of David Bowie's " Space Oddity" and hang out with lonely robots.

After reading the excerpt from "A Hitchhiker's Guide to the Galaxy," Cristoforetti waved a white towel and let it float around inside in honor of Towel Day. We're pretty sure this might be the geekiest and coolest way any fan has celebrated the day. Adams would approve.