Elon Musk will work on the U.S. Space Force’s low Earth orbit communication “backbone.”
Yesterday, the U.S. Space Force announced the award of a $2.29 billion contract to SpaceX, Musk’s aerospace company, for the construction of a network of satellites in low Earth orbit, intended to serve as military internet in space.
The non-traditional fixed-price contract covers the Space Data Network (SDN) backbone, a resilient network architecture designed to connect military sensors and weapon platforms worldwide.
The SDN Backbone, formerly known as Milnet and based on the militarized Starshield variant of SpaceX’s commercial Starlink constellation, will serve as the backhaul data transport layer for the broader SDN, explains Breaking Defense.
Among other functions, the SDN will provide communication channels for the integration and transfer of data from missile warning and tracking sensors to interceptors in near real-time, a capability considered critical for the Golden Dome, the missile shield project announced a year ago by the U.S. president, regarded as a priority of the Trump administration.
All the details.
WHAT IS THE SPACE DATA NETWORK
The SDN backbone is a constellation of satellites in low Earth orbit (pLEO) that will expand a satellite network to provide communication services globally, the Pentagon stated. It will work alongside the Space Development Agency’s Transport Layer to form a unified architecture that will deliver critical data transport for current and future Department of Defense missions.
“The SDN backbone leverages the best of commercial innovation and provides a solid foundation for the SDN mission series, a huge advantage and an enabler for our military,” said Space Force Colonel Ryan Frazier, interim acquisition portfolio lead for the program.
Specifically, the SDN backbone will serve as the “backhaul” layer of the architecture. In telecommunications terms, backhaul refers to the high-capacity transfer of data between distributed networks. The satellites will transmit large amounts of military data between spacecraft, sensors, command systems, and weapon platforms, explains Spacenews.
SPACEX WILL UTILIZE STARSHIELD SATELLITES
To build the system, SpaceX will use its Starshield satellites, a variant designed for government needs of the commercial broadband Starlink constellation. According to Musk’s company, Starshield leverages Starlink technology to provide secure satellite networks designed for national security missions.
CAPACITY CONCENTRATED UNDER A SINGLE CONTRACTOR?
As Spacenews also points out, the move has raised concerns because it concentrates a significant portion of future satellite contracts under SpaceX, whereas previous SDN acquisitions for the transport layer were distributed among several companies.
In response, the Space Force stated it intends to identify additional contractors for satellite construction and other network elements over the summer.
ESSENTIAL ARCHITECTURE FOR GOLDEN DOME
As mentioned, this architecture is increasingly linked to the Pentagon’s Golden Dome missile defense initiative, a multi-layered defense system designed to track and shoot down advanced missile threats using a combination of space sensors, communication networks, and interception systems.
Military officials consider the SDN a critical component because it would allow missile tracking satellites to rapidly transmit targeting data through orbital relay networks to command systems or interceptors with minimal delay.
For example, a satellite detecting a missile launch could transmit tracking information through the SDN mesh network directly to missile defense systems or combat units, creating what military planners call “sensor-to-shooter” connectivity.
THE ROADMAP
The Space Force has stated that the provider must deliver a fully operational SDN backbone prototype by the end of 2027.
Meanwhile, General Michael Guetlein, the U.S. Space Force officer responsible for the Golden Dome project, has estimated the cost of the first phase at $185 billion, an increase of $10 billion. The increase was attributed to the request to “acquire additional space capabilities,” he said.
President Trump has indeed requested that Golden Dome be “fully operational” by 2028, a timeline Guetlein has contested. He stated he wants to demonstrate “operational capability” by that year but is considering 2035—six years after the end of Trump’s second term—for the version that will fit within the $185 billion cost structure.
