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Not Enough Sats? Starlink Director Throws Shade at Rival AST SpaceMobile

A senior director of satellite engineering at SpaceX raises doubts about AST SpaceMobile's satellite constellation and its ability to beam data to phones without interruption.

 & Michael Kan Principal Reporter

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(Credit: AST SpaceMobile)

A director at SpaceX is questioning rival AST SpaceMobile’s plan to bring satellite connectivity to phones, casting doubt about the company’s technology and approach.

In a tweet on Wednesday, Ben Longmier, senior director for satellite engineering at SpaceX, disputed how AST has said it only needs 45 to 60 company satellites to offer nationwide coverage for the US. According to Longmier, AST’s network simply won’t be large enough, resulting in spotty signal quality. 

“The notion that AST will cover the US with continuous data with 60 sats is incorrect. No one wants bursty data separated by tens of minutes of 0 bps,” he wrote

SpaceX is developing its own satellite-to-phone service via cellular Starlink. The company has already kicked off beta tests with T-Mobile users, delivering satellite connectivity to iPhones and Samsung devices using a growing constellation of over 400 satellites.

The 400 satellites have already shown they can power SMS messages to phones based in cellular dead zones, although the signal quality can be inconsistent. SpaceX is also working (and lobbying) to bring voice calls and data downloads to the satellite network.

In another tweet, Longmier added: “We want to launch a couple hundred more sats so that the whole US has a high-quality data experience. No user will tolerate long gaps in data coverage. Any LEO [low-Earth orbiting] operator needs many hundreds of sats for this type of coverage.”

(Credit: AST SpaceMobile/SpaceX)

AST SpaceMobile didn’t immediately respond to a request for comment. But the tweets from Longmier highlight the growing rivalry between the two companies. In October, SpaceX also accused AST of spreading misinformation to the FCC while deriding it as a “meme stock” out to derail progress on the company’s cellular Starlink technology.

On the technology front, SpaceX has talked about operating thousands of cellular Starlink satellites in the coming years, similar to the home internet-focused Starlink business. In contrast, AST has talked about a smaller constellation spanning 60 larger satellites, although the company previously filed for regulatory authority to operate up to 243

So far, AST has only launched five of its “BlueBird” satellites, which recently gained FCC approval to start operational tests. However, each BlueBird is exceptionally large, with a 700-square-foot communication array capable of beaming high-speed data and powering video calls. 

To improve the signal quality further, the company is preparing second-generation BlueBird models that promise to be 3.4 times larger and deliver a 10 times boost in capacity. Both AT&T and Verizon have signed up to use the company’s technology, while a vocal group of stock investors has been touting AST as the future leader in mobile satellite connectivity. 

Hence, the public can expect more debates and regulatory spats over which company’s technology performs best, especially as T-Mobile aims to move the cellular Starlink system out of beta and to a mainstream release later this year.

About Our Expert

Michael Kan

Michael Kan

Principal Reporter

My Experience

I've been a journalist for over 15 years. I got my start as a schools and cities reporter in Kansas City and joined PCMag in 2017, where I cover satellite internet services, cybersecurity, PC hardware, and more. I'm currently based in San Francisco, but previously spent over five years in China, covering the country's technology sector.

Since 2020, I've covered the launch and explosive growth of SpaceX's Starlink satellite internet service, writing 600+ stories on availability and feature launches, but also the regulatory battles over the expansion of satellite constellations, fights with rival providers like AST SpaceMobile and Amazon, and the effort to expand into satellite-based mobile service. I've combed through FCC filings for the latest news and driven to remote corners of California to test Starlink's cellular service.

I also cover cyber threats, from ransomware gangs to the emergence of AI-based malware. In 2024 and 2025, the FTC forced Avast to pay consumers $16.5 million for secretly harvesting and selling their personal information to third-party clients, as revealed in my joint investigation with Motherboard.

I also cover the PC graphics card market. Pandemic-era shortages led me to camp out in front of a Best Buy to get an RTX 3000. I'm now following how the AI-driven memory shortage is impacting the entire consumer electronics market. I'm always eager to learn more, so please jump in the comments with feedback and send me tips.

The Best Tech I've Had:

  • My first video game console: a Nintendo Famicom
  • I loved my Sega Saturn despite PlayStation's popularity.
  • The iPod Video I received as a gift in college
  • Xbox 360 FTW
  • The Galaxy Nexus was the first smartphone I was proud to own.
  • The PC desktop I built in 2013, which still works to this day.

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