WASHINGTON — The billionaire backing a series of private astronaut missions with SpaceX says the first of those flights will likely be delayed to some time in 2024.

In a recent interview with the CNBC Manifest Space podcast, Jared Isaacman said preparations were continuing for Polaris Dawn, the first of three missions of his Polaris program announced in early 2022. That mission will fly Isaacman and three others on a Crew Dragon spacecraft that will spend several days in low Earth orbit.

“We’re making a lot of progress. We’re still hoping for the end of the year, but I suspect it will probably slip into the beginning of next year,” he said in the brief interview. “This should be expected. It’s a test and development program.”

When Isaacman and SpaceX announced Polaris in February 2022, they scheduled the Polaris Dawn mission for as soon as the fourth quarter of 2022. However, by last October the launch slipped to at least March 2023, which the program attributed to readiness of the vehicle and training as well as the schedule of other Crew Dragon missions.

In a talk at a conference in February, Isaacman said he expected Polaris Dawn to launch this summer. “We’re now just months away from flying,” he said then. The program has not provided any formal schedule updates about the mission since then, with the most recent update on the program’s website published in May.

A delay beyond the end of this year would likely push Polaris Dawn later than the beginning of 2024. Axiom Space is planning its third private astronaut mission to the International Space Station in January 2024, followed as soon as a month later by NASA’s Crew-8 mission to the station, both using Crew Dragon spacecraft. While Polaris Dawn is not going to the ISS, availability of Crew Dragon spacecraft and other resources needed for crewed missions could delay Polaris Dawn to later in the year.

Isaacman, in the podcast interview, suggested the delays were linked to the development of a new spacesuit required for a spacewalk, the first by a private astronaut mission, planned for Polaris Dawn.

“We’ve had a little bit more free time this summer than we probably would have expected,” he said, which he attributed to the timing of spacesuit development and training. That effort “doesn’t always sync up, so we’ve had a little more free time with family and work this summer.”

That new suit, billed as the first new spacesuit developed in the United States in four decades, is critical to future human activities on moon and Mars, he argued. “We’re going to need spacesuits that don’t cost hundreds of millions of dollars in order to do that. We’re pretty excited because the suit that we are testing out, the evolution of it someday could be very well worn by people that are walking on the moon or Mars.”

However, it’s not clear when that SpaceX-developed spacesuit would next be used. NASA awarded contracts in June 2022 to Axiom Space and Collins Aerospace for development of spacesuits to both replace those currently used on the ISS as well as for future Artemis lunar landing missions. While SpaceX’s Starship will be used for at least the Artemis 3 and 4 missions to land on the lunar surface, those missions will use spacesuits from Axiom or Collins.

Polaris Dawn is the first of three missions in a program that will culminate in the first crewed launch of Starship. That final mission is “pretty far out there,” Isaacman said, noting that SpaceX still had a lot of progress to make on Starship before flying people on it. “Clearly it’s going to need a lot more launches and that design is going to have to evolve to the extent that it’s going to be safe for human spaceflight.”

Since the announcement of the Polaris program, one option that has emerged for the second mission is a Crew Dragon flight to reboost the Hubble Space Telescope. Isaacman participated in a NASA briefing last September that announced an unfunded Space Act Agreement between NASA and SpaceX to study such a mission.

NASA has not disclosed the outcome of that effort, but confirmed in May that the study was complete and that the agency was “internally evaluating the findings and working to determine next steps.” The agency also received eight responses to a separate request for information from companies developing satellite servicing technologies that could reboost Hubble.

Isaacman said on the podcast that the ball was in NASA’s court about a Crew Dragon mission to Hubble. “There are obviously a lot of important things that being discussed right now at NASA, but hopefully they will get around to this proposal and perhaps we’ll have a pretty exciting Polaris 2 to follow,” he said.

At a NASA Science Mission Directorate town hall meeting July 27, Mark Clampin, director of NASA’s astrophysics division, said NASA was still evaluating options for raising Hubble’s orbit. “Part of that review means looking at the capabilities of the Hubble Space Telescope itself and how this would work,” he said, “and make sure the telescope itself remains safe during the process.” He did not state when that review would be completed.

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...