Inspiration4's Hayley Arceneaux Says Historic Space Mission 'Changed Me in Unexpected Ways'

Inspiration4 The Inspiration4 crew in the Dragon's cupola

It's been a month since Hayley Arceneaux returned from space, and now the Inspiration4 Medical Officer is opening up about her out-of-this-world experience in her final astronaut diary for PEOPLE. Though the 29-year-old has a career as a physician assistant at St. Jude Children's Research Hospital in Memphis, Tennessee, where she beat cancer at the age of 10, Arceneaux added astronaut to her resume by training for the first all-civilian mission into outer space alongside billionaire Jared Isaacman (the Shift4 Payments CEO who sponsored the SpaceX flight), Christopher Sembroski and Dr. Sian Proctor. Together they worked to "inspire support for the lifesaving work of St. Jude," the hospital said of its $200 million fundraising goal. The crew delivered, and then some, having raised $238 million in commitments. Keep reading for Arceneaux's thoughts as she processes the history-making mission, and click here to read all of her diary entries.

My journey to space changed me in unexpected ways. When I saw Earth from the glass cupola for the first time, I was overwhelmed with gratitude — gratitude for being alive to see it, but also for getting to see something that so few people have seen from that perspective. Just over 70 women have gone to space, and to be in that small group is something I never felt I deserved, but it was an opportunity that I was able to seize, and I hope many others will too.

Also, seeing the planet from that distance and the landmasses without borders filled me with a new perspective into how much we are all united as Earthlings. The feeling of viewing our Earth with its complete and absolute beauty and peace is difficult to put into words. I cried the last time I was in the cupola looking at Earth because I knew it was likely the last time I'd ever see it from that perspective, and I was incredibly overwhelmed emotionally with how much gratitude I felt in that moment.

SpaceX Inspiration4 crew

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Since my return, people have been asking me if I was nervous at liftoff. Truthfully, I was incredibly calm. I kept thinking that maybe at different phases of launch day the nerves would hit, like when I strapped into the capsule or when they were counting down from 10. But those nerves never came because our training prepared us so well, and my crewmates and I just felt so ready. We actually played music and cracked jokes during the two and a half hour wait after being strapped in before liftoff. When liftoff did happen, the nine-minute ride up to space was actually very smooth, I couldn't believe it.

Once in space I noticed how great my leg felt. Throughout the three days in orbit, I was doing flips constantly. Eating cold pizza while doing flips. Drinking water and flipping. Doing my research while flipping. Because I could! I felt like, "These are the only three days I'll get to float like this, so let me do as many flips as possible while I can." The day I got back, reentry day, my orthopedic surgeon texted me and asked how the leg did and I said it was absolutely perfect.

I'm proud I was able to use my medical training in orbit as the medical officer. The reality is that there are physiologic changes with going to space that affect the majority of people. It's not surprising that some of the crew members became nauseated. Fortunately, I was able to help them by administering shots to mitigate it. It was more difficult than I expected to draw up the medication from a vial in space because of the medication floating and moving in the vial, but I was able to use techniques learned in training to get the job done.

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The highlight of the trip and a highlight of my life was the video call we had with former and current patients of St. Jude. I was so excited to share my experience with them. Several of the kids on that call were my own patients, and it was incredible to hear from them because they inspire me so much on a daily basis. Hearing their voices from space was especially motivating. Throughout this mission, it has been an incredible honor to represent cancer patients and survivors, so I made sure this call would happen and I could show what their future could look like, whether they want to be astronauts or whatever big dream they want to come true. On the call I was able to show them the capsule, do some flips and answer their sweet questions. One of my favorites: "Are their cows on the mooooon?" As much as this call meant to me, I love that my crew members got so much out of the call too. They said it was one of their highlights of the whole mission and especially meaningful to them as they've all worked so hard fundraising for St. Jude and being advocates alongside me.

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Upon reentry, when the main parachutes deployed prior to landing, we all shouted with joy. We were so excited because we knew at that point everything was going to be okay. As we hit the water, we heard and felt this big wave from the splashdown, but we couldn't see it because the windows were fogged from the atmosphere entry.

St. Jude Children's Research Hospital/YouTube Inspiration4 crew speaking with St. Jude patients

When we landed in the ocean, Jared called Mission Control and said, "Inspiration 4, mission complete." About an hour later, after reuniting with our families and while going through medical evaluations, we found out that Elon Musk was donating $50 million, which helped us surpass the mission's fundraising goal of $200 million for St. Jude. That was incredibly emotional, because at that point it was not just mission complete, instead it was mission accomplished. I am so proud of everyone who helped us reach this goal and now I'm eager to see where Inspiration4 continues to go from here, especially for the ongoing lifesaving research and work at St. Jude. I just know we're going to be experiencing the impact of Inspiration4 for many years to come. In the meantime, life for me now means getting back to work at St. Jude with my patients, doing non-space things like laundry, hanging with my dog, and eating my favorite foods I couldn't eat in orbit — like queso!

Episodes of Countdown: Inspiration4 Mission To Space are available on Netflix now. To learn more about St. Jude Children's Research Hospital, the Inspiration4 mission and ways you can support, visit stjude.org/inspiration4 and listen to the podcast St. Jude Mission of a Lifetime. Fans can also follow Hayley's on Instagram and Twitter.