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SpaceX launches 21 satellites to orbit for the US military after 5-day delay (video)
The satellites will help fill out the Proliferated Warfighter Space Architecture network in Earth orbit.
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SpaceX just sent another batch of satellites to orbit for the U.S. military.
A Falcon 9 rocket lifted off from California's Vandenberg Space Force Base today (Oct. 10) at 3:39 a.m. EDT (0739 GMT; 12:39 a.m. local time), hauling 21 "data transport" satellites to orbit for the U.S. Space Force's Space Development Agency (SDA).
That was five days later than originally planned. SpaceX tried to launch the mission on Monday (Oct. 5), but the Falcon 9 aborted that attempt in the countdown's final minute, for reasons that the company has not disclosed.
Today's launch helps build out the SDA's Proliferated Warfighter Space Architecture (PWSA), which SpaceX describes as "a mesh network of optically connected satellites in low Earth orbit [LEO] that enable global military tactical communications and missile warning, indication and tracking capabilities."
The liftoff was the fourth of nine that SpaceX will conduct to help assemble the architecture's Tranche 1 — the "initial warfighting capability tranche," according to the SDA.
Tranche 1 will eventually consist of 154 operational satellites in LEO — 126 data-transport spacecraft and 28 missile-tracking vehicles. There will also be four missile-defense test satellites, which will sport a "higher fidelity" infrared sensor than their tracking counterparts, SDA officials wrote. (Missile-tracking satellites generally hunt for the heat signatures these weapons produce during flight).
Eighty-four of the 126 data-transport satellites have now launched to date, all of them on Falcon 9s, which lifted off from Vandenberg in September 2025, October 2025, July of this year and today.
And, as its name suggests, Tranche 1 will be just the beginning, if all goes according to plan.