The U.S. Space Force isn’t slowing down. Not even slightly.
The agency just signed deals for 36 new satellites. The price tag? $1.75 billion. The goal is simple, if terrifying: spot incoming missiles from space before they become a problem. These spacecraft will join the “Golden Dome,” the Trump administration’s high-profile initiative to harden American defense against hypersonic and ballistic threats.
Two companies are doing the heavy lifting here. L3Harris Technologies and Sierra Space each get a contract for 18 spacecraft. All 36 are slated to be ready for launch by the end of next year. 2028 is the deadline.
This is part of a larger push. Specifically, the Space Development Agency’s Proliferated Warfighter Space Architecture. We are talking about the Tracking Layer of Tranche 3. It’s a hybrid missile-defense system. Its job? To provide what officials call “global stereo coverage.”
Why two companies?
You might wonder why the government split the order. The contracts are distinct. They serve slightly different roles within the same network.
Sierra Space gets a deal worth up to $798 million. They will build 18 “missile warning and missile tracking variant” space vehicles. These will ride on the Horizon bus, derived from the Eclipse series. Sierra used similar tech for Tranche 2. It’s an incremental upgrade. Familiar hardware, hardened for a tougher mission.
L3Harris gets the bigger slice of the pie. Their contract tops out at $955 million. They are building 18 “missile defense variant” spacecraft. These look like the Hypersonic and Ballistic Tracking Space Sensor (HBTSS) platforms L3Harris has been refining for the Missile Defense Agency. They’ve already got five of these things in orbit. They have over 70 missile satellites on order across all Tranches. They know this system inside out.
Both sets of satellites use infrared sensors. That’s non-negotiable. You can’t see hypersonic glide vehicles with regular optics. You need heat. You need IR.
How does the Tracking Layer actually work?
The satellites sit in low Earth orbit. They scan the globe. When a missile launches, the infrared eyes pick up the heat signature.
Here is the tricky part. Detection is one thing. Tracking is another.
The new satellites don’t just see. They talk. They push that data in real time. Low-latency laser links connect them to other nodes in the network. Eventually, that data reaches military forces on the ground. Commanders see the trajectory. They get the warning. They have seconds to act.
“This expands upon SDA’s previous… generations,” said SDA Director G.P. Sandho. He called it a “milestone.” Words matter less than the result: resilience. If one satellite dies, another sees it. That’s the point of proliferation. Too many targets for an adversary to bother shooting down.
The bigger picture
This latest batch isn’t standing alone. In December 2025, the SDA already ordered 72 more Tranche 3 spacecraft. That was a $3.5 billion deal involving L3Harris, Lockheed Martin, Rocket Lab, and Northrop Grumman.
Add the new 36 to those 72. You get 108 satellites. The total value of that combined effort? About $5.25 billion.
That is a lot of hardware. And a lot of risk.
Space is crowded. Debris is a constant headache. And if these satellites fail to launch, the timeline crumbles. The SDA calls these contracts “accelerated.” But they haven’t published a strict launch timeline for the whole group yet. We know the deadline is late 2029 for the full set. The new ones might launch sooner. Hope is not a strategy, though.
Once they are up there, the Space Force takes over. The Space Development Agency built them. The Space Force runs them. They integrate into joint operations. They provide the warfighting capability the military desperately wants.
Is it enough?
The Golden Dome initiative faces scrutiny. Critics point to cost overruns and technical hurdles. Hypersonics are notoriously difficult to track. They move too fast. They maneuver unpredictably. A satellite network helps, but it isn’t a silver bullet.
Still, the trend is clear. America is building a wall in the sky. A digital wall made of lenses and lasers and code.
Who builds the rest? Lockheed Martin. Northrop Grumman. Others will follow. The supply chain is stretching. Can it handle the volume? L3Harris seems prepared. Sierra Space is catching up. But 108 satellites require flawless execution.
One failure can delay the whole layer.
The world is watching. China and Russia are building their own counterspaces capabilities. They want to blind our eyes. The Space Force’s answer is to multiply them. Make the network too big to kill.
We’ll see if it holds. The next few years of launches will tell the truth. Not the press releases. The truth.
