APRIL 23

NASA and Elon Musk's commercial rocket company SpaceX launched a new four-astronaut team on a flight to the International Space Station on Friday, the first crew ever propelled into orbit by a rocket booster recycled from a previous spaceflight.

The company's Crew Dragon capsule, Endeavour, streaked into the darkened pre-dawn sky atop a SpaceX Falcon 9 rocket as its nine Merlin engines roared to life at 5:49 a.m. (0949 GMT) from NASA's Kennedy Space Center at Cape Canaveral, Florida. The blastoff was aired live on NASA TV.

The crew is due to arrive at the space station, which orbits some 250 miles (400 km) above Earth, early on Saturday following a flight of about 23 hours.

Within 10 minutes of launch, the rocket's second stage had delivered the crew capsule to Earth orbit, traveling at nearly 17,000 miles per hour, according to launch commentators.

The rocket's first stage, meanwhile, descended back to Earth and touched down safely on a landing platform floating in the Atlantic on a drone ship affectionately named Of Course I Still Love You.

The mission marks the second 'operational' space station team to be launched by NASA aboard a Dragon Crew capsule since the United States resumed flying astronauts into space from U.S. soil last year, following a nine-year hiatus at the end of the U.S. space shuttle program in 2011.

It is also the third crewed flight launched into orbit under NASA's fledgling public-private partnership with SpaceX, the rocket company founded and owned by Musk, the billionaire entrepreneur who is also CEO of electric carmarker Tesla Inc.

The first was an out-and-back test mission carrying just two astronauts into orbit last May, followed by SpaceX's first full-fledged four-member crew in November.

Friday's Crew 2 team consists of two NASA astronauts - mission commander Shane Kimbrough, 53, and pilot Megan McArthur, 49 - along with Japanese astronaut Akihiko Hoshide, 52, and fellow mission specialist Thomas Pesquet, 43, a French engineer from the European Space Agency.

The four helmeted crew members, dressed in their white flight suits and black boots, were briefly glimpsed seated side by side in the capsule just after reaching orbit in a video clip captured by an onboard camera.

LONG-DURATION MISSION

They are expected to spend about six months aboard the orbiting research platform conducting science experiments and maintenance before returning to Earth.

The four members of Crew 1, sent to the space station in November, are slated to fly home on April 28.

The Crew 2 mission made a bit of spaceflight history due to the fact that its Falcon 9 rocket blasted off with the same first-stage booster that lofted Crew 1 into orbit five months ago, marking the first time a previously flown booster has ever been re-used in a crewed launch.

Reusable booster vehicles, designed to fly themselves back to Earth and land safely once they separate from the rest of the rocket minutes after launch, are at the heart of a re-usable rocket strategy that SpaceX helped pioneer to make spaceflight more economical.

SpaceX has logged dozens of successful Falcon 9 booster return landings, and the company has refurbished and re-used most of them, some for multiple flights. But all of those flights, until Friday's mission, only carried cargo.

Crew 2's pilot, McArthur, made a bit of history herself as the first female pilot of the Crew Dragon and the second person from her family to ride aboard the SpaceX capsule. She is married to NASA astronaut Bob Behnken, who flew the SpaceX demonstration flight with fellow astronaut Doug Hurley last year. The same Crew Dragon was used for that flight as well.

If all goes well, McArthur and her three crewmates will be welcomed aboard the space station Saturday by the four Crew 1 astronauts - three from NASA and one from the Japan Aerospace Exploration Agency JAXA. Two Russian cosmonauts and a U.S. astronaut who shared a Soyuz flight to the space station are also aboard.