The Pentagon on Tuesday announced about $2.5 billion in contracts will go to , and Sierra Space to build satellites for an expanding military system.

The U.S. Space Force's Space Development Agency is having the trio of companies build 54 satellites as part of a network the U.S. military is building, . These satellites will be for the "Tranche 2 Tracking Layer" of the satellite constellation, related to missile defense.

Under the awards, each company will build 18 satellites — 16 for missile warnings and tracking, and two with missile defense infrared sensors. The fixed-price contracts are worth $919 million for L3Harris, $890 million for Lockheed Martin and $740 million for Sierra Space. The satellites are expected to launch in April 2027.

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"The agile response across the space industry is critically important as we deliver to the warfighter this no-fail mission capability of missile warning, missile tracking, and missile defense," SDA Director Derek Tournear said in a statement.

PWSA is a constellation designed to have hundreds of satellites in orbit, for greater resiliency and redundancy than previous U.S. military satellites. It is being built out in "tranches," and each will represent a new generation of satellites with increasing capabilities. Each tranche consists of two "layers:" Transport, for mesh communications, and Tracking, for targeting locations and missile defense.

The Pentagon has increased its ambitions in space, seeing a need to in a domain that has widespread ramifications for national security efforts back on Earth. The Space Force has especially seen its budget grow, with $30 billion requested for fiscal 2024, about double its budget from 2021. Much of that funding goes to defense contractors and space companies providing products and services to the military.

The SDA has previously awarded contracts to build and operate satellites for the same network to Lockheed and L3Harris, as well as , SpaceX, York Space and .

Sierra Space is a privately held spinoff from Colorado-based aerospace and defense contractor Sierra Nevada Corporation. Late last year, after shipping its first Dream Chaser spaceplane.

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