The company’s stock was down more than 12% as of 10:15 a.m. ET after the company announced plans to sell up to $500 million in common stock.

That was a big shift from pre-market hours, before the announcement, when shares were moving 7% higher (adding $841 million in value to the company at the time). Even with the fall, though, Virgin Galactic shares have nearly doubled year to date.

The announced stock sale comes after a marketing coup for the company. Millions of people watched the VSS Unity fire its rocket engine and accelerate to faster than three times the speed of sound Sunday – as well as the subsequent celebrations. That could boost interest in passenger ticket sales—when those become available.

The seats won’t be cheap. Prices for the 600 reservations already sold range from $200,000 to $250,000 each. Some analysts believe the prices could go even higher, though—perhaps even doubling.

Branson might have been the first billionaire to ride a ship of his company’s own making to the edge of space, but he won’t be the last. Amazon founder Jeff Bezos is scheduled to go even higher next Tuesday, July 20, on a Blue Origin rocket.