A US aerospace and defense company has recently launched 21 satellites into low Earth orbit, in a bid to help the military detect missiles and communicate securely during missions.The satellites were deployed on October 10, 2026, aboard a SpaceX rocket for the US Space Development Agency (SDA). They are the first Northrop Grumman-built satellites for the agency’s Tranche 1 Transport Layer (T1TL).The project is part of a larger military satellite network known as the Proliferated Warfighter Space Architecture (PWSA). It aims to detect and track missile threats, and allow military forces to exchange critical information around the world with almost no delay.Lou Christen, Northrop Grumman senior director of proliferated systems, praised the milestone. “Our first plane of Transport Layer satellites strengthens the PWSA constellation by adding capacity and diversity of an on-orbit asset, helping SDA accelerate toward global, resilient, instant connectivity for the joint force,” he said. Stronger space defenseThe 21 satellites are expected to improve secure communications and information sharing between US troops, military equipment, as well as other satellites. One of their main functions is to bring Link 16, a secure, encrypted, high-speed, and jam-resistant military data network, into space.Link 16, which is mainly used by NATO members and other nations, allows military forces to exchange tactical information, such as data about potential threats. The satellites could extend its reach into space and allow troops to receive important updates significantly faster.Northrop Grumman elaborated that the satellites will provide secure, low-latency communications and back the network’s missile warning and tracking capabilities. The Transport Layer will also connect with a separate constellation of satellites to spot and track conventional and advanced missiles.The firm is also contracted to supply over 30 satellites for SDA’s missile tracking network. “The company is combining advanced technology and deep mission experience in military satellite communications and responsive ground solutions to for this next-generation constellation in low Earth orbit,” Northrop Grumman said.SpaceX’s roleThe satellites were reportedly carried aboard a SpaceX Falcon 9 rocket that lifted off from Vandenberg Space Force Base in California, at about 12:39 am local time, on Saturday, October 10. The launch came five days after an earlier attempt was canceled with just 58 seconds remaining in the countdown due to unusual data from the rocket’s second stage.In the latest mission, the Falcon 9 delivered all 21 satellites into orbit, bringing the total number of Tranche 1 spacecraft in space to 84. This was the fourth launch during the first phase of SDA’s military satellite program.Northrop Grumman expects to launch another 21 satellites soon. The firm aims to deploy dozens more within six months. It is also building around 150 satellites for the program’s first three phases, Tranches 1, 2 and 3.“We’ve fully embraced the rapid go-to-market strategy and are on contract to deliver approximately 150 innovative satellites for the warfighter, a key capability for an integrated, layered defense system,” Christen said in a press statement. To build satellites faster, Northrop Grumman uses modern assembly lines and AI-powered tools across its seven million square feet of facilities. It also uses ready-made parts alongside its own technology to cut costs.