SpaceX is making another attempt to get Polaris Dawn — a risky mission that will send four civilians into the radiation belts and on a historic spacewalk — off the ground this week.
The daring flight will aim to take off from Kennedy Space Center in Florida no earlier than 3:38 a.m. ET Tuesday, with additional launch opportunities at 5:23 a.m. ET and 7:09 a.m. ET Tuesday. A SpaceX webcast of the event is expected begin around midnight the morning of the liftoff.
Additional launch opportunities are available in the early hours of Wednesday morning, according to SpaceX.
Previous attempts in late August to launch the Polaris Dawn mission were thwarted by a ground system issue at the launch site and weather delays. And weather could again prevent the unprecedented journey from kicking off Tuesday.
The latest forecast puts the odds of unfavorable launch conditions at 60%, according to a Sunday post made by SpaceX on X, the social media platform formerly known as Twitter.
Mission controllers are also closely watching the weather outlook off the coast of Florida, where the Polaris Dawn crew will splash down at one of several locations after its five-day trip to space.
“(C)onditions at the possible splashdown sites for Dragon’s return to Earth remain a watch item,” according to SpaceX.
Despite the forecasts, Jared Isaacman, the billionaire founder of payment platforms company Shift4, said Sunday on X, “This is a big improvement over the last two weeks. We are getting closer to getting this mission to orbit.”
Isaacman, who is both funding this mission alongside SpaceX and a crew member serving as mission commander, previously made clear how crucial it is for Polaris Dawn to take flight with pristine weather conditions on the horizon for the crew’s return.
Because the team will rely heavily on oxygen supplies during preparations for and while executing a spacewalk, the Polaris Dawn mission will have only about five or six days’ worth of oxygen supplies on board, necessitating an on-time return, according to Isaacman.
The spacewalk, which is scheduled to kick off at the start of the Polaris Dawn crew’s third day of flight, will mark the first time that a private crew of civilians has carried out extravehicular activities, or EVA, in space.
A perilous journey
Joining Isaacman on this flight are close friend and former US Air Force pilot Scott “Kidd” Poteet as well as SpaceX engineers Anna Menon and Sarah Gillis.
Adding to the risk of the Polaris Dawn team, the crew cabin will travel out into the first band of Earth’s Van Allen radiation belts after the mission takes flight — the first human spaceflight mission to travel that far since NASA’s Apollo program ended in 1972.
SpaceX is also juggling Polaris Dawn with other obligations at its launch site in Florida.
The company is expected to help get NASA’s Europa Clipper — a notable robotic mission set to explore an icy moon orbiting Jupiter — on its way in October.
But SpaceX’s launch site in Florida is currently set up for a crewed spaceflight — with the pad configured for a SpaceX Falcon 9 rocket, Crew Dragon and the special crew access arm that allows astronauts to board the vehicle before flight.
Before Europa Clipper gets off the ground, SpaceX will have to convert the launchpad to accommodate a Falcon Heavy, a larger vehicle that has three times more power than a Falcon 9.
NASA is expected to give an update on the Europa Clipper mission at 4 p.m. ET Monday.