The company listed directly on the NYSE, following the closing of a merger last week with Chamath Palihapitiya's venture Social Capital Hedosophia.
"Virgin Galactic is making history again today as it becomes the world's first and only publicly traded commercial human spaceflight company," CEO George Whitesides said in a statement. "For the first time, anyone will have the opportunity to invest in a human spaceflight company that is transforming the market."
Shares of Virgin Galactic rose as high as $12.93 but closed the day down just 0.3% at $11.75. The shares were previously listed under the ticker IPOA for Palihapitiya's special purpose vehicle, which took a 49% stake in Virgin Galactic. Shares of Palihapitiya's venture closed at $11.79 a share on Friday, up nearly 12% in the past three months.
"Healthy traction, but still early days," MKM Partners analyst Rohit Kulkarni said in a note to investors. MKM Partners did not participate in the offer and did not began covering the stock with a recommendation.
In essence, Monday's debut represented a name change for the company, as investors could trade shares of Palihapitiya's venture since before the merger was announced.
"If the public want to dabble a little bit in a spaceship company, own a little bit of a spaceship company, they can now do so," Branson said on CNBC's "Squawk on the Street."
Special purpose vehicles, also known as SPACs, raise capital to buy an existing company. In Social Capital Hedosophia's case, Palihapitiya's SPAC acquired just under half of the company to help it enter the public market. Palihapitiya is the founder of Social Capital and had been an early executive at Facebook.
Branson has said he plans to retain his 51% controlling stake after the debut.
Palihapitiya sees Virgin Galactic as "a business that has software-like margins," telling CNBC in July that he believes there is a "really compelling risk-reward" behind space tourism. UBS, in a March report, estimated that space tourism has a potential market of $3 billion a decade from now, even though it's "still at a nascent phase."
With a price tag of $250,000 per person, Virgin Galactic plans to carry as many as six passengers in its spacecraft at a time. Flown by two pilots, spaceship is dropped from a jet-powered aircraft and fires a rocket motor, reaching over three times the speed of sound as it climbs though the Earth's atmosphere. Then the spacecraft and its passengers float weightless for a few minutes, before gliding back down to land on Earth much like a traditional aircraft.
After years of delays, Virgin Galactic is in the final stages of testing its spacecraft. The company has a list of 603 customers who have paid deposits, some of whom have been waiting for a decade for their chance to fly.
"Because it's taken so long to get this far I try not to think about the fact that we're almost there because I have thought about that for a few years," Branson told CNBC earlier this month.
The company plans to begin flying commercial flights in 2020.
Virgin Galactic has testing facilities in California's Mojave Desert and an agreement with Spaceport America in New Mexico for the first commercial flights. But Branson says that's just the beginning for the space tourism business, as the company is talking about expanding across several continents.
"Abu Dhabi would like us to do a spaceport there, and we're in discussions with them," Branson said. "Italy would like us to do a spaceport there. Great Britain wants us to do a spaceport. Australia talked to us about doing a spaceport."
Virgin Galactic is also looking to begin operations "in a few other, Asian countries," Whitesides said. But perhaps the most fascinating opportunity may be in Scandinavia, where the company is speaking to Sweden about flying into the region's spectacular night sky.
"We've talked about going up into the Northern Lights," Branson said. "It would be ridiculous."
As for the company's first commercial flights, Branson expects to be on the first one — yet left it a mystery as to who else will fly with him.
"We have an announcement to make, so I'm not allowed to talk about it," Branson said. "Sometime next year, I will be taking somebody up, but I will have to let you know."