Starlink is SpaceX's big cash cow. And it just reported some mixed results. SpaceX said its satellite-internet service had 13.6 million consumer subscribers at the end of September, up 1.6 million from three months earlier. That fell short of the 14.2 million expected by Bloomberg analysts. Still, Starlink is making a lot of money. Monthly consumer revenue per user rose 5% from the previous quarter, while enterprise and government revenue jumped 91% from a year earlier to $2.1 billion. A big, important customer? Airlines. The company said that, as of the end of September, 3,800 total aircraft had been outfitted with Starlink equipment.

The company has recently focused on becoming a mobile provider. On October 8, SpaceX announced it had agreed to buy a portfolio of low-band wireless spectrum from Grain Management. The deal gives SpaceX a key ingredient that could turn its Starlink satellite-internet provider into a direct challenger to Verizon, AT&T, and T-Mobile. SpaceX said the spectrum would power Starlink Mobile, which it has described as a hybrid satellite-and-terrestrial network designed to work indoors, outdoors, and in cellular dead zones.

It also comes after SpaceX hinted that it saw itself as a challenger to mobile carriers during its first-ever earnings call in August. The company's president, Gwynne Shotwell, hinted that the company was considering building a "cellular base station on basically the gear that holds the Starlink broadband dish," rather than a ground-based system. They said the market was worth $600 billion annually. "I anticipate us to be able to acquire quite a few of their customers," Shotwell said.