The Inspiration4 astronauts are stoked to launch on their history-making SpaceX mission

The Inspiration4 crewmembers — Chris Sembroski, Jared Isaacman, Hayley Arceneaux and Sian Proctor — seen at the rollout of the Falcon 9 rocket and Crew Dragon capsule that will carry them to orbit.
The Inspiration4 crewmembers — Chris Sembroski, Jared Isaacman, Hayley Arceneaux and Sian Proctor — seen at the rollout of the Falcon 9 rocket and Crew Dragon capsule that will carry them to orbit. (Image credit: Inspiration4/John Kraus)

CAPE CANAVERAL, Fla. — SpaceX's private Inspiration4 mission is cleared for launch and the flight's four crewmembers are excited to blast off today (Sept. 15) to embark on a three-day journey around Earth

LIftoff is set for sometime during a five-hour window that opens at 8:02 p.m. EDT (0002 GMT on Sept. 16). The crew's ride to space will be a veteran Falcon 9 rocket that previously ferried two different GPS satellites into space for the U.S. Space Force. For its third act, the rocket will carry a Crew Dragon spacecraft with the first all-civilian crew strapped inside. Jared Isaacman, Hayley Arceneaux, Sian Proctor and Chris Sembroski will spend approximately three days in space as part of an effort to raise millions for St. Jude Children's Research Hospital. Before launch, the crewmembers said they're incredibly lucky to be a part of this mission and are ready to go to space. 

"We're very aware of how lucky we are, to be part of this history that that SpaceX is creating right now," Isaacman told reporters during a prelaunch news briefing held on Tuesday (Sept. 14). "Without their efforts, there wouldn't be an Inspiration4 mission today."

Related: SpaceX's Inspiration4 private all-civilian orbital mission: Live updates
More: Inspiration4: SpaceX's historic private spaceflight in photos

Isaacman is the mission's commander and founder of Shift4 Payments, which earned him the money to purchase the flight from SpaceX. He donated the other three seats as part of his mission to raise $200 million for St. Jude. 

Isaacman is joined by Arceneaux, who is a childhood cancer survivor and currently a physician assistant at the very hospital that saved her life, St. Jude. "I want to thank Jared and SpaceX for allowing this mission to be possible and for raising awareness for St. Jude," Arceneaux said during the news conference. "We couldn't be more excited about the mission."

Arceneaux is the flight's medical officer and she says she's looking forward to the bevy of medical experiments the crew will be performing while in space. The data collected will help researchers better understand how the human microbiome changes during spaceflight. Because the flight is on a trajectory that will take the crew further into space than the International Space Station or the Hubble Space Telescope, they will also do studies on space radiation. 

Meanwhile, the mission is also setting records. Arceneaux will become the youngest American to reach space; her crewmate Proctor will become the first Black female pilot and only the fourth Black female astronaut.

Proctor said she wants to use her experience to inspire others to pursue their dreams of spaceflight. "I am really excited to launch on this mission because I have this opportunity to not only accomplish my dream, but also inspire and inspire the next generation of women of color and girls of color and really get them to think about reaching for the stars and what that means," Proctor said during the news conference. 

Sembroski says that being a part of the mission is a huge honor for him. He won his spot by making a donation to St. Jude. from a commercial he watched during the Super Bowl earlier this year. And actually, his name wasn't picked out of the donors, his friend's name was and that friend gave the seat to Sembroski. 

"I think that just really puts me in a very special spot where not only do I feel very lucky to be here, but I have a huge responsibility to, you know, pay that forward and show generosity towards others," he said before launch.

When asked if they were nervous at all, the crew collectively said no. 

"I was always worried that this moment would never come in my life, so I'm ready to go," Proctor said. "Let's do it."

The crew has been training for about six months, including logging many hours in SpaceX's Dragon simulator. 

"To prepare for the flight, this crew has been doing a significant amount of astronaut training," Isaacman said. "We put in hundreds of hours at SpaceX, studied over 90 different kinds of training guides and manuals and lessons to learn how to fly the fly the Dragon and what to do in emergency situations."

That work has paid off, he said. "We're ready to go."

While it's been all business here on the ground in preparation for their historic launch, the crew is also looking forward to some of the more fun aspects of space travel, including revealing their zero-g indicator, which is traditionally a stuffed animal of some sort that floats about the cabin once the crew has reached space. 

For example, during the Demo-2 mission that marked SpaceX's crewed test flight, NASA astronauts Bob Behnken and Doug Hurley took a blue and pink sequined dinosaur to space; the four astronauts who flew on the first full-fledged SpaceX mission brought a stuffed Baby Yoda with them. 

"When we’re up in orbit, the first thing we will be excited to do is reveal what our zero-g indicator is and how that connects back to our overall mission," says Isaacman. "That's gonna be the first way we celebrate being in space."

The crew will get to enjoy a special menu while in orbit which includes cold pizza, per Proctor's request. "Food and mood are so important," she said. "So I think for us, it was really important working with SpaceX, to get food that made us feel comfortable, and that we could eat and they've done a great job of accommodating that because I think we're all really happy and the food is going to be great."

The rest of the menu is still under wraps, but Inspiration4 representatives say that the crew will definitely show off their food in orbit. 

While the Inspiration4 crew is looking forward to experiencing spaceflight, they are also looking forward to having the time to reflect on their journey. The past few months have been packed, with very little downtime as they prepped for their journey to space. 

"We've just been going supersonic, from one training event to another," Isaacman said. "That's why we made a documentary so that, you know, when this thing's over, we have a chance to look back on everything we've experienced and kind of remember those good memories, as well as connect with all of you." 

Arceneaux echoed that sentiment, saying that the past several months have just been a whirlwind. 

"When we were here with you in February, it just felt far away and kind of abstract," she said. "Now, our rocket is behind us and we're flying in less than 24 hours. It's just so much more real and just so exciting."

Follow Amy Thompson on Twitter @astrogingersnap. Follow us on Twitter @Spacedotcom or Facebook.

Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at:

Amy Thompson
Contributing Writer

Amy Thompson is a Florida-based space and science journalist, who joined as a contributing writer in 2015. She's passionate about all things space and is a huge science and science-fiction geek. Star Wars is her favorite fandom, with that sassy little droid, R2D2 being her favorite. She studied science at the University of Florida, earning a degree in microbiology. Her work has also been published in Newsweek, VICE, Smithsonian, and many more. Now she chases rockets, writing about launches, commercial space, space station science, and everything in between.