TRUTH OR CONSEQUENCES, N.M. -- Richard Branson reached the edge of space and landed successfully after a flight aimed at spurring a new, multibillion-dollar space-tourism industry.

The British entrepreneur and five crew members crossed the threshold on a test flight of the spacecraft developed by $Virgin Galactic Holdings Inc(SPCE.US)$, which climbed more than 50 miles above the Earth's surface.

The spacecraft VSS Unity landed back at the Spaceport America facility in New Mexico on Sunday after a flight lasting about an hour. It successfully separated from the launch plane VMS Eve, which took off after a weather delay, before its onboard rocket fired and sent it higher.

At the peak, Mr. Branson and other crew members unbuckled and experienced weightlessness and peered at Earth and into space from a dozen windows in the cabin.

The flight is part of a broader push from companies and investors to develop viable businesses based on human space flight, long dominated by government space agencies with scientific and policy missions. There have been instances of private space-tourist trips in the past, such as the investor Dennis Tito's 2001 visit to the International Space Station, but building a private industry around such travel has proved elusive for commercial enterprises so far.

A number of entrepreneurs aim to change that. $Amazon.Com Inc(AMZN.US)$'s founder, Jeff Bezos, has been investing in his space company, Blue Origin LLC, which plans to take him and three others to space on a company rocket later this month. Elon Musk's Space Exploration Technologies Corp., or SpaceX, plans to fly the chief executive of a payments company to space this year.

On Friday, Blue Origin took aim at Virgin Galactic, posting a graphic on Twitter that said its New Shepard rocket has the largest windows in space, in contrast to those available on Virgin Galactic's "high altitude airplane."

Blue Origin said it is flying to the Karman Line, a boundary some 62 miles above Earth considered to be the start of space by many. The Federal Aviation Administration defines space as starting at 50 miles, the so-called Armstrong Line.

"New Shepard flies above both boundaries. One of the many benefits of flying with Blue Origin," Blue Origin said in another tweet. A Virgin Galactic spokeswoman declined to comment about the tweets.

Mr. Bezos on Saturday used his Instagram account to wish Mr. Branson "and the whole team a successful and safe flight. Best of luck!" On Twitter, Mr. Musk said he would be on site in New Mexico for the Virgin Galactic trip.

Mr. Branson on Sunday posted a photo on Twitter of himself standing with Mr. Musk, the Tesla Inc. chief executive. "Feeling good, feeling excited, feeling ready," Mr. Branson said.

On Sunday morning ahead of takeoff, the Spaceport America facility had the feel of a festival, with guests of Virgin Galactic eating food and listening to a DJ, who at one point tried to get a dance contest started and reminded people to put on sunscreen. Some guests, wearing purple "Unity 22" T-shirts -- Sunday's flight is the 22nd for the VSS Unity----milled in and out of a building for the event and near a stage set up outside. A band occasionally warmed up. Later, the musician Khalid is scheduled to perform. Around 500 guests are in attendance, including Mr. Musk and New Mexico Gov. Michelle Lujan Grisham, a company spokeswoman said.

Space tourism could generate close to $4 billion in annual revenue by 2030, according to an estimate last year from UBS. Human space flight carries risks, and the vehicles developed by private space companies have been tested a fraction of the number of times compared with the planes used by airlines.

Virgin Galactic has said it plans to initiate commercial space flights that generate sales in 2022. The company founded by Mr. Branson has reported 600 reservations for future flights backed by $80 million in deposits. It reported a loss of $273 million for last year and, compared with Blue Origin and SpaceX, has a business model that is more deeply tied to the emergence of a space-tourism sector.

The company hasn't disclosed what it will charge for tickets when it starts selling them again, but prices are likely to be out of reach for most people for some time. Mr. Musk is one of the ticket holders, according to a spokesman for Virgin Galactic. In the past, the company has sold tickets for up to $250,000 each, according to its latest annual report. Virgin Galactic interrupted marketing efforts in 2014 after a pilot died testing a company space plane.

Kerrianne Flynn, a Virgin Galactic customer who attended the event, said she signed up in December 2011 for a space flight. She is unsure when she will eventually get to make the trip but added the wait has been worth it. "There's going to be nothing like going up there," she said.

The Spaceport Facility, which was constructed using funds from New Mexico and local tax dollars, should help foster the state's economy, Gov. Lujan Grisham said. "We're on the map," she said.

Virgin Galactic has described Sunday's flight as part of its testing program. Now the company is focused on thinking through the experience of private astronauts it brings to space, Chief Executive Michael Colglazier said in a recent interview.

Sunday's flight will include Mr. Branson; Beth Moses, chief astronaut instructor at Virgin Galactic; Colin Bennett, a lead operations engineer at the company; and Sirisha Bandla, a Virgin Galactic vice president focused on government affairs and research.

"Richard's got this long history of creating transformative consumer experiences," Mr. Colglazier said. "He's been dreaming about this for years, and we needed one of the members of this four-person crew in the back to really just absorb and focus on the experience side of it. He was perfectly suited to that."

Dave Mackay and Michael Masucci will fly the VSS Unity, while CJ Sturckow and Kelly Latimer will fly the VMS Eve plane, according to the company.

During a trip in May, the spacecraft reached 55.5 miles of altitude and met the company's technical objectives. Last month the FAA approved a full commercial space-launch license for the company.

Mr. Branson, 70 years old, is behind a business empire that includes airlines, cruise ships, hotels and gyms. In recent years, Mr. Branson has made his space businesses, which include the satellite-launch company Virgin Orbit, his main focus.

Write to Micah Maidenberg at micah.maidenberg@wsj.com and Doug Cameron at doug.cameron@wsj.com