CAPE CANAVERAL, Fla. — SpaceX's next astronaut launch is just four days away. On Wednesday (Sept. 15), a crew of four private citizens will strap into a Crew Dragon spacecraft and blast off on a three-day journey around the Earth dubbed Inspiration4.
Here are the top 10 things you need to know about the mission.
1) First non-professional spaceflight
For the first time, a group of four private citizens — and zero professional astronauts — will climb into SpaceX's Crew Dragon spacecraft to launch into space. This is SpaceX's fourth crewed mission, but instead of astronauts representing NASA and its international partners, the passengers will be four regular people.
All previous orbital space tourism flights (and planned such missions with announced crews) have included at least one professional astronaut to guide the passengers through the drama of launch, microgravity and landing.
2) Meet the crew
The mission's commander is Jared Isaacman, a billionaire who founded Shift4 Payments and purchased the flight.
He is joined by Hayley Arceneaux, a physician assistant at St. Jude Children's Research Hospital, where she was also once a patient. Arceneaux, who will serve as the flight's medical officer, is a pediatric bone cancer survivor. She will be the first person to fly in space with a prosthesis, as she has a metal rod in her leg to replace bone removed due to a tumor.
Sian Proctor, the mission's pilot, is a geosciences professor at South Mountain Community College in Arizona and a science communicator who has dreamed of going to space since she was a child. Proctor's father worked for NASA at a tracking station in Guam during the Apollo 11 mission that landed the first humans on the moon. Proctor applied to be a NASA astronaut for the class of 2009, but was ultimately not selected. She thought her dreams of going to space would never come true, until she got the call from Inspiration4.
Chris Sembroski is an Air Force veteran who works for aerospace giant Lockheed Martin. He is a former Space Camp counselor and will be a mission specialist for the flight. Sembroski won the seat after making a donation to St. Jude through a fundraising campaign organized as part of Inspiration4.
3) Fundraising efforts
The Inspiration4 mission is part of an effort to raise $200 million for St. Jude Children's Research Hospital. Isaacman didn't want just another billionaire spaceflight on the books, he wanted the mission to really mean something, so he led a campaign to raise money and awareness for childhood cancer research.
Isaacman donated $100 million directly to St. Jude, as well as two of the other seats on the Dragon spacecraft. One went to Arceneaux, whom the hospital selected as a frontline worker. The other seat was designated to a winner randomly chosen from sweepstakes entries that raised $13 million for the cancer institute. Sembroski was selected after a friend of his (who was technically chosen) decided not to go to space.
Proctor won her seat through a "Shark Tank"-like contest that set up online stores using Isaacman's Shift4 Payments platform as a way to raise money for St. Jude. Each contestant had to set up a shop and campaign on Twitter. The more interaction their videos received on Twitter, the more likely they were to make it to the finals.
4) When is it launching?
Inspiration4 is facing a 24-hour launch window that opens on Sept. 15 at 8 p.m. EDT (midnight on Sept. 16 GMT). Mission personnel will narrow that schedule down to a five-hour window just a few days before launch.
The mission can launch any time according to representatives from SpaceX and Inspiration4, but the exact liftoff time will be chosen based predominantly on weather forecasts for both launch and landing sites from the 45th Weather Squadron.
4) Where is the crew going?
The crew will not be going to the International Space Station, but will instead free-fly around Earth. That's a different itinerary than the capsule's previous journey, when it ferried astronauts to the orbiting laboratory.
Without any need for a docking port on the spacecraft, SpaceX replaced that structure with a dome window that will provide the crew with breathtaking views of Earth.
6) How long will they be in space?
The crew will stay in space for approximately three days before splashing down off the coast of Florida.
7) What will the crew be doing?
Because the Inspiration4 mission consists entirely of regular people, not professional astronauts, they have not undergone the same rigorous medical disqualification process that NASA and other agencies follow during astronaut selection. So throughout the mission, the Inspiration4 crewmembers will perform a variety of medical experiments and record health data to support future human spaceflights.
8) Where are they launching from?
Inspiration4 will launch from Pad 39A at NASA's Kennedy Space Center in Florida. This is one of two launch pads that SpaceX operates in Florida, and the same one that hosted the company's three previous crew mission launches.
Before being turned over to SpaceX, Pad 39A also supported the majority of NASA's space shuttle missions, which flew between 1981 and 2011. And it's also the same launch pad that Neil Armstrong, Buzz Aldrin and Michael Collins launched from as part of the historic Apollo 11 moon mission that saw Armstrong and Aldrin become the first humans to walk on the moon.
9) How will they get to space?
Isaacman, Arceneaux, Proctor and Sembroski will strap into a Crew Dragon spacecraft perched atop a Falcon 9 rocket — both of which have flown before.
The rocket, dubbed B1062, has flown twice before as it carried GPS satellites into space for the U.S. Space Force. The Dragon capsule is the same one that ferried the Crew-1 mission — NASA astronauts Mike Hopkins, Victor Glover, Shannon Walker and Japanese astronaut Soichi Noguchi — into space last November and back to Earth six months later.
10) What will they take with them?
Since Inspiration4 is part of a massive fundraising effort, the crew will be taking items up with them to be auctioned off, as well as personal items.
Some of those items include mission jackets featuring artwork made by St. Jude patients, a Fisher Apollo 11 50th Anniversary Space Pen and Coin Set containing a piece of material from Apollo 11, a ukulele from Martin Guitar that Chris Sembroski will play in space, and much more, according to a mission statement.
In addition, Arceneaux will play a non-fungible token, or NFT, of a never-before-released performance by the band Kings of Leon during the flight. Another NFT onboard will replicate a piece of art that previously went to the Mariana Trench, making it the first artwork to reach both the deepest part of the ocean and orbit.
Follow Amy Thompson on Twitter @astrogingersnap. Follow us on Twitter @Spacedotcom or Facebook.
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Amy Thompson is a Florida-based space and science journalist, who joined Space.com 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.