NASA officials gave the go-ahead on Friday for SpaceX and the agency to continue preparations for a historic liftoff of two astronauts on a rocket from Florida to the International Space Station next week.

The launch, scheduled for 4:33 p.m. on Wednesday from NASA’s Kennedy Space Center, may be the start of a new era in spaceflight, one in which NASA relies on private companies like Elon Musk’s SpaceX to launch astronauts — a task it used to handle itself.

President Donald Trump suggested on Thursday that he might attend the launch.

As during the space shuttle era, NASA conducts what it calls a flight readiness review about a week before launch to ensure that the spacecraft and launch systems are ready and that any significant concerns have been resolved.

While the mission is proceeding smoothly, the decision to move forward came amid new turmoil at NASA. The head of the agency’s human spaceflight program, Douglas Loverro, unexpectedly quit on Monday, six months after he took the job. Loverro, who was to lead the flight readiness review on Friday, said in an interview with The Washington Post that his departure had nothing to do with next week’s mission but that it added to doubts about the Trump administration’s pledge to return astronauts to the moon by 2024.

This is the second upheaval in less than a year. In July, Jim Bridenstine, the NASA administrator, reassigned William Gerstenmaier, who had led the agency’s human spaceflight program since 2005.

For nearly nine years, after the retirement of the space shuttles, the United States has relied on Russia to provide transportation of astronauts to and from the International Space Station. NASA had been developing its own new rocket, called the Ares I, but with cost overruns and delays, the Obama administration decided that it would be cheaper and faster to turn to private companies. In 2014, NASA chose Boeing and SpaceX, with hopes that the first launches would occur by 2017.

Using SpaceX’s Crew Dragon and Boeing’s Starliner capsule did prove much cheaper than NASA’s original plan, but was perhaps no faster in terms of development.

NASA is looking to take a similar commercial approach to its next moon missions. The agency recently chose to finance design work on three lunar lander proposals that may be used for a 2024 mission. Loverro’s resignation on Monday may involve those contracts.

This article was written by Kenneth Chang, a reporter for The New York Times.