Tesla (TSLA) and SpaceX CEO Elon Musk took a moment this week to celebrate a major milestone for Starlink, the satellite internet service that's trying to do something ambitious: rebuild the internet in orbit. The service just crossed 9 million customers worldwide, and Musk had some thoughts on what that means.

Space Internet Is Hard, Actually

Starlink's official account announced Monday that the service now serves customers in 155 countries, territories, and various other markets. Musk responded with characteristic understatement on X: "Rebuilding the whole Internet in space is not easy." Fair enough. Most people can't get their home Wi-Fi to work reliably in the basement, so launching thousands of satellites to beam internet globally does seem moderately challenging.

A Rare Hiccup and Mobile Ambitions

Speaking of challenges, one of Starlink's satellites recently experienced what the company called a "rare failure." The satellite was cruising at about 260 miles above Earth when it lost communications and generated some debris in orbit. According to Starlink, the satellite will reenter Earth's atmosphere within weeks.

But SpaceX isn't slowing down. The company recently filed for a "STARLINK MOBILE" trademark with the USPTO, which has everyone wondering if Starlink is planning to become a cell carrier. The trademark filing describes "two-way real-time transmission" of voice, audio, video, and data through wireless telecommunications devices. That sounds a lot like, well, a phone company.

SpaceX already has partnerships in place with existing carriers. There's a deal with T-Mobile US Inc. (TMUS) to offer direct-to-cell technology to subscribers, and an agreement with Ukrainian telecom giant Kyivstar Group Ltd. (KYIV) as well.

Starlink-Connected Teslas?

Tesla recently filed an intriguing patent called "Vehicle Roof Assembly with Radio Frequency Transparent Material." The patent describes vehicle roofs made with radio frequency transparent polymers, which could allow antennae to be integrated directly into the roof structure. The result? Direct communication with satellites and other connected technology. If you're wondering whether your future Tesla might come with built-in Starlink connectivity, this patent suggests that's not entirely far-fetched.