California: Virgin Galactic, the venture founded by British billionaire Richard Branson, is set to launch its first commercial flight to the edge of space after setbacks and delays -- a milestone two decades in the making, Al Jazeera reported.

Two Italian air force officers and an aerospace engineer from the National Research Council of Italy will join a Virgin Galactic instructor and the spaceplane's two pilots on a suborbital ride on Thursday.

The flight named Galactic 01, will take 90 minutes. It comes two years after Virgin Galactic's first, fully crewed test spaceflight of its VSS Unity rocket plane, according to Al Jazeera report.

Virgin Galactic makes use of a "mothership" aircraft carrying two pilots that take off from a runway, gain high altitude, and then deploy the rocket-powered VSS Unity that flies into space at nearly Mach 3 before flying back to Earth.

Passengers in the space plane's cabin will experience a few minutes of weightlessness. During the scheduled trip on Thursday, they will be able to catch a glimpse of the planet's curvature.

A live stream of the flight will start at 15:00 GMT on the website of the company, Al Jazeera reported.

Virgin Galactic tweeted, "TOMORROW, we're launching The Spaceline for Earth with #Galactic01, our first scientific research mission! You can watch the moment live at 9:00 am MDT | 11:00 am EDT. Sign up so you don't miss it: http://virgingalactic.com."

As per the news report, Virgin Galactic has sold around 800 tickets for its commercial flights. As many as 600 tickets were sold between 2005 to 2014 for USD 200,000 to USD 250,000 while 200 have been sold since then for USD 450,000 each, according to Al Jazeera report.

Film actors and other celebrities were among the first to book seats. However, the company's programme suffered a disaster in 2014. The company's space plane on a test flight broke apart midair, resulting in the death of the co-pilot and seriously injuring the pilot, the report said.

Virgin Galactic has said that the company's next scheduled commercial flight dubbed Galactic 02 is planned for August. The monthly flights to space are expected to be sold following that launch.

The company is competing in the "suborbital" space tourism sector with US billionaire Jeff Bezos firm Blue Origin. The company has already sent 32 people into space.

However, Blue Origin's rocket has been grounded since an accident in September 2022, Al Jazeera reported. The company in March committed to resuming spaceflight soon.

Moreover, SpaceX, the rocket and satellite company led by Elon Musk, flew a crew of private astronauts on a three-day orbital trip in September 2021.

Virgin Galactic's launch comes amid heightened awareness of high-stakes tours undertaken by wealthy adventurers after the loss of an OceanGate Expeditions submersible bound for the Titanic wreckage in the Atlantic Ocean last week.

Five people died, including three who had purchased tickets that cost about USD 2,50,000 each, according to the company's website.