The world’s first spaceship designed for tourists exploded in midair and crashed to the floor of the Mojave Desert on Friday, killing one test pilot, severely injuring another, and leaving the young industry of commercial space rattled and heart­broken.

SpaceShipTwo was supposed to become a shuttle to space for Virgin Galactic, the company founded by celebrity entrepreneur Richard Branson.

It was an elegant spacecraft, with a narrow body and flashy wings, and it had been handcrafted in a hangar at the Mojave Air and Space Port, about 95 miles north of Los Angeles. The company had hoped to start commercial flights soon, rocketing passengers above the atmosphere at a ticket price of up to $250,000 a seat.

It was unclear what Friday’s disaster will do to those ambitions or to the fledgling industry that has grown up around the desert town of Mojave. For commercial space, this day will be akin to what happened to NASA in 1967 when the Apollo 1 spacecraft had a capsule fire, killing three astronauts, during a launch test.

“Space is hard. And today was a tough day,” said a visibly shaken George Whitesides, the chief executive of Virgin Galactic and a former chief of staff at NASA.

The company offered no explanation for the disaster, which is being investigated by federal aviation officials. This was the fourth powered flight of the spaceship, all at relatively low altitudes, well within the atmosphere. But it was the first powered flight since January. It used a new fuel mix that had been tested on the ground successfully, said Kevin Mickey, president of Scaled Composites, which built the vehicle for Virgin Galactic.

“Ignition! #SpaceShipTwo is flying under rocket power again. Stay tuned for updates,” Virgin Galactic tweeted at 1:07 p.m. Pacific time.

But soon thereafter came the ominous follow-up: “#SpaceShipTwo has experienced an in-flight anomaly.”

The spacecraft was found ripped apart, in large fragments, amid the sagebrush on the desert floor.

“From my eyes and my ears, I detected nothing that appeared abnormal,” Stuart Witt, the Mojave Air and Space Port’s chief executive, said of the launch at a news conference Friday afternoon. He later added, “If there was a huge explosion that occurred, I didn’t see it.”

A photographer captured images, carried by CNN, showing the spacecraft firing its rocket engine and then, moments later, disintegrating amid a white cloud of vapor or smoke and leaving a trail of debris in the blue desert sky.

This has been a terrible week for commercial space in general: An Antares rocket, topped by a Cygnus capsule loaded with supplies for the International Space Station, exploded Tuesday night seconds after liftoff from a launchpad at Wallops Island, Va. Investigators from NASA and Orbital Sciences Corp., the Dulles, Va., company that owned the rocket and had a contract for multiple cargo missions to the space station, continue to look into the incident.

SpaceShipTwo falls to Earth

As bad as that explosion was, the crash of SpaceShipTwo was a greater tragedy, taking the life of a pilot who was identified by the Kern County coroner’s office Saturday as 39-year-old Michael Alsbury, of Tehachapi, Calif., the Associated Press reported . His body was found inside the wreckage, the AP said. A second pilot ejected and was found at the crash site by emergency teams, who took him to Antelope Valley Hospital in Lancaster, Calif. His condition and identity had not been made public late Friday.

The crash was a devastating blow to the most high-profile start-up devoted to space tourism.

Virgin Galactic has been hoping to be the pioneer of space tourism, taking customers nearly 70 miles above Earth’s surface on short, suborbital flights. There is no absolute edge to space, because the atmosphere thins gradually, but it is generally agreed that such an altitude, where space appears black, easily qualifies.

For many years, the company has been promising that it is getting close to commercial operation, but it has faced a series of delays because of technical issues — not an uncommon problem in spaceflight.

SpaceShipTwo was designed by the legendary engineer Burt Rutan, who founded Scaled Composites in Mojave, a rustic town near Edwards Air Force Base. It is a part of the country known for historic aviation feats, among them pilot Chuck Yeager breaking the sound barrier in 1947.

A smaller predecessor to the craft, SpaceShipOne, became the first private spacecraft to reach space in 2004. Scaled Composites is no stranger to tragedy, having suffered a hangar explosion in 2007 in Mojave that killed three people and critically injured three others.

A person who answered the phone at Rutan’s home said no one could comment.

“We’re going to get through it,” Whitesides said at the news conference. “The future rests in many ways on hard, hard days like this. But we believe we owe it to the folks who were flying these vehicles as well as the folks who’ve been working so hard on them to understand this and to move forward, which is what we’ll do.”

SpaceShipTwo was an eight-seat craft, including two seats for the pilots. The vehicle was not designed to launch like a conventional rocket or space shuttle. Instead, it rode to an altitude of about nine miles underneath a jet-powered carrier plane, the WhiteKnightTwo. That craft then dropped the winged spaceship, which would glide for a few seconds before its rocket engine would fire. The company planned to use that rocket thrust to eventually go all the way to space.

The spaceship would then glide back to Earth and land on a runway. The beginning of commercial service has been continuously pushed back, but the company had said such flights could become a reality in 2015.

Branson had vowed to fly on the first flight and take his son along. The company said that the British tycoon was en route to Mojave.

“This will inject a note of sobriety into the enthusiasm of those who would like the spaceflight experience,” said John Logsdon, professor emeritus at George Washington University’s Space Policy Institute. “There was a whole juggernaut of ground training and private spaceports that were being set up to support an emerging space tourism industry, with a collective burst of maybe unrealistic expectations. This will certainly throw cold water on that.”

Sen. Bill Nelson (D-Fla.) released a statement saying he was deeply saddened by the death of the pilot. “This has been a tragic week for our commercial space sector,” he added.

Charles Lurio, the publisher of a newsletter about the commercial space industry, compared Friday’s test-flight disaster with the incidents that cost hundreds of people their lives in the early years of aviation.

“I hope people understand that in order to make progress in certain areas, you have to take certain risks,” Lurio said. “This is why we need more than one or two companies trying things out, and why we need people willing to test things on the ground.”

At the Voyager Airport Restaurant, a diner in the spaceport right under the control tower, employees said they were stunned to learn of the explosion.

“It’s very, very sad,” said owner Joudi Alsaady. “I guess that’s part of life. If you want to reach the stars, you’ve got to pay the price sometime.”

Abby Phillip, Mark Berman and Sarah Larimer contributed to this report.