The Space Development Agency announced contracts worth $1.75 billion to build 36 satellites in support of the Pentagon’s Golden Dome missile defense shield.
The satellites will be part of Tranche 3 of SDA’s missile defense, warning, and tracking layer, a constellation of satellites in low Earth orbit. L3Harris and Sierra Space both received contracts to build 18 satellites each and deliver them in time for a potential launch in late 2028.
“With these awards, SDA is accelerating the deployment of the Tracking Layer to provide the homeland,
our deployed forces, and allies with global, persistent indications, detection, identification warning,
tracking, and defense against advanced and evolving missile threats,” SDA Director GP Sandhoo, who is also the Space Force’s Portfolio Acquisition Executive for Missile Warning and Tracking, said in a July 13 statement.
The Space Force awarded initial contracts for Tranche 3 last December to Lockheed Martin, Rocket Lab, Northrop Grumman, and L3Harris for a total of 72 satellites. This additional batch of 32—which SDA calls Accelerated Missile Defense Tranche 3, or AMDT3—brings the total tranche to 104 spacecraft.
SDA said in its statement that L3Harris’ satellite design will be based off the Hypersonic Ballistic Tracking and Space Sensor. L3Harris and Northrop Grumman each built one HBTSS prototype for the Missile Defense Agency, both of which launched as part of the first batch of SDA missile defense satellites.
“The new contract builds on the successful on-orbit demonstration of an L3Harris Hypersonic and Ballistic
Tracking Space Sensor (HBTSS) satellite and infrared sensor payload the company developed for the
Missile Defense Agency,” L3Harris CEO Chris Kubasik said in a statement, adding that the company has more than 70 missile tracking and defense satellites on order.
Sierra Space’s satellites will be missile warning/missile tracking spacecraft. The company said in a statement that the satellites will be based on its “Horizon” spacecraft. The company is already on contract to build 18 satellites for Tranche 2 of SDA’s tracking layer.
“By combining cutting-edge design and manufacturing systems with industrial depth and systems integration expertise, we’re able to move faster, manage risk better and deliver more cost-effective solutions,” said Sierra Space CEO Dan Jablonsky in a statement. “AMDT3 is proof that our approach is working, and we’re just getting started.”
Golden Dome Director Michael Guetlein said in March that his program, intended to shield the U.S. from missiles, added $10 billion to its total price tag to “accelerate” some of the space-based sensing elements of its architecture.
Lawmakers have called for the Pentagon to move quickly to buy more missile warning and tracking satellites. The Senate Armed Services Committee included language in its draft of the fiscal 2027 National Defense Authorization Act that would require SDA to field at least 45 HBTSS-like satellites as part of Tranche 3.
“In the spirit of the Acquisition Transformation Strategy’s focus on delivering capability at speed and scale, embracing proven capabilities that are ready now, the committee directs the U.S. Space Force to prioritize acquisition and operational deployment of a full constellation of at least 45 space vehicles equipped with proven HBTSS payloads,” the committee wrote in a report accompanying the bill.