In Florida on Sunday, a SpaceX-built rocket and capsule will transport crew members to the International Space Station. NASA’s mission comes on the heels of a successful demonstration of the same spacecraft that launched in May and brought two astronauts back to Earth in August. Here’s what you need to know about the launch.

What is the launch of SpaceX?

Four astronauts – three from NASA and one from the Japanese space agency JAXA – will sit inside the SpaceX Crew Dragon capsule, boosted to orbit over a Falcon 9 rocket. The mission is known as Crew-1, and the astronauts have dubbed their capsule flexibility. They are heading to the International Space Station for six months.

This is the first of what NASA calls “operational” flights for the Dragon Crew. In May, there was a demonstration mission, with two NASA astronauts – Robert Behnken and Douglas Hurley – on board. This launch, in a capsule called Endeavor, was the first time a manned mission had set off from the United States into orbit since the retirement of the NASA Space Shuttle in 2011. Its return also marked the first astronaut water landing on a US spacecraft since the Apollo capsules stopped. Aviation in the 1970s.

NASA was relying on Russian Soyuz rockets to transport its astronauts to the space station. It’s becoming increasingly expensive, as the cost of the seat has risen to over $ 90 million.

When is the launch date?

The Crew-1 mission is scheduled to launch Sunday at 7:27 PM ET from the Kennedy Space Center in Florida. NASA TV Coverage will be broadcast starting at 3:15 pm

Astronauts will arrive at the space station at around 11 p.m. ET on Monday, for a journey that will take about 27 hours.

Projections currently give a 50 percent chance of favorable conditions on the launch pad. SpaceX and NASA are also watching farther in the Atlantic. The weather and water there should be fairly calm in case something goes wrong while climbing into orbit and the Crew Dragon needs to do. Emergency machine gun (Bad weather has pushed back the previous launch date Saturday.)

If the launch is delayed on Sunday, there is a backup opportunity on Wednesday.

Who are the astronauts?

Michael S Hopkins, 51, a colonel in the US Space Force, is the commander of the flight. (Colonel Hopkins is also the first member of the newly created US Space Force to go into space.) He was one of the nine astronauts selected by NASA in 2009. He made one previous trip to the International Space Station, in 2013 and 2014, spending 166 days in orbit.

Shannon Walker, 55, spent one previous mission on the space station, in 2010. Dr. Walker received her Ph.D. in space physics from Rice University, where she studied how the solar wind interacts with the atmosphere of Venus.

Soichi NoguchiA 55-year-old astronaut with Japan’s space agency JAXA will make his third trip into space. He was a crew member of the Space Shuttle Discovery in 2005 at the shuttle’s first launch after losing Columbia and its seven astronauts more than two years earlier.

During that visit to the International Space Station, Mr. Noguchi made three space trips. This included testing of technologies developed to repair thermal tile damage on the shuttle similar to what wiped out Colombia when it returned to Earth’s atmosphere. In 2009 and 2010, he spent five months in orbit as a member of the space station crew.

Victor GloverThe 44-year-old, chosen by NASA in 2013 as an astronaut, will make his first spaceflight. He will be the first NASA black astronaut to serve on a space station crew. Mr. Glover’s achievement is noteworthy for NASA, which has worked to highlight:Hidden figures“In its history, but so far only 14 black Americans out of a total of more than 300 NASA astronauts have been sent.

He will not be the first black astronaut aboard the station. But those who sent him from NASA were members of the space shuttle crews during construction of the station and only completed short stays at the site.

Alison Waller contributed reporting.