SpaceX stock was lower on Thursday. Shares have been volatile since the record-setting June IPO, but this drop likely stems from a Starship disappointment.

Starship is SpaceX's huge, fully reusable rocket designed to dramatically cut costs to reach orbit. It is hard to overstate the importance of Starship. Lower costs are key to applications such as data centers in space, which SpaceX believes will give it a huge AI advantage over players with only data centers on the ground.

Starship is in testing. The 13th test in July was a success. The 14th test, likely later this month, was to feature a catch of the rocket's upper stage with huge mechanical arms. SpaceX caught the lower stage in a 2024 test, which was an amazing feat of engineering. (Catching the rocket aids in rapid reusability.)

CEO Elon Musk, however, said on Thursday that a catch of the upper stage isn't imminent.

"Looks like we will probably catch the ship with the tower in a few months," he posted on X. "If there had been a tower out to sea where we practiced landing the ship, it would have been caught."

Delays in Starship development have the power to affect SpaceX stock. Shares were down 6.4% in midday trading at $130.66, below the $135 IPO price. The S&P 500 was off 0.5%.

Still, the reaction could be an overreaction.

"Although the Starship catch timing has been shifted, Starship is making progress toward the monumental achievement of full rocket reusability, which is a significant step toward achieving rapid reusability," wrote William Blair analyst Louie DiPalma in a Thursday report. "SpaceX is likely a full decade ahead of peers on this front, so a delay by a few months is not that consequential."

He rates shares Outperform and doesn't have a price target. A Buy at Blair essentially means the broker expects the stock to outperform the market.

SpaceX hopes to be launching its Starmind AI computing satellites as soon as 2027. It likely needs Starship to do that, so the Starship development issue isn't going away any time soon.