What happened

Shares of Virgin Galactic Holdings (SPCE -12.17%) stock tumbled on Friday afternoon after SpaceX and rival space tourism company Axiom Space confirmed the successful liftoff of their Ax-1 mission, sending four private astronauts to spend a week at the International Space Station (ISS).

Virgin Galactic shares are down 2% as of 1:50 p.m. ET on the news.

Two of Ax-1's crew of four astronauts walking to board a SpaceX Crew Dragon en route to ISS.

Image source: SpaceX.

So what

Axiom tweeted out the successful launch of Ax-1 at 11:18 a.m. ET, confirming that its four astronauts had achieved zero gravity 15 minutes later, and had begun their 20-plus hour trip to ISS, with arrival anticipated sometime around 7:45 a.m. ET tomorrow.  

Axiom described the Ax-1 mission as "a new chapter" in spaceflight, and NASA said it "takes commerce to a whole new level," opening up the ISS to commercial businesses to conduct experiments in space -- and blazing a trail to the eventual construction of private space stations in orbit.  

The company already has three more missions lined up to advance this goal -- Ax-2, Ax-3, and Ax-4 -- and expects those to launch to ISS "approximately every six months, subject to NASA approval."

Now what

So what does all of this mean to Virgin Galactic, as its small fleet of spaceplanes sits stubbornly, silently stuck to the tarmac down at Spaceport America in New Mexico? Simply this:

As companies like Blue Origin launch tourists regularly to the edge of space, and SpaceX sends tourists on orbital trips round the Earth -- and helps Axiom send still more tourists on destination trips to the space station -- Virgin Galactic's once groundbreaking "space tourism" business looks increasingly obsolete.

If Virgin Galactic investors are feeling a bit discouraged about its lack of progress today, I cannot say I blame them.