Explainer-How the US tracks ballistic missile launches

FILE PHOTO: Residents walk at a site of a Russian missile strike, amid Russia's attack on Ukraine, in Dnipro, Ukraine November 21, 2024. REUTERS/Mykola Synelnykov/File Photo

SINGAPORE (Reuters) - The United States has layers of sensors that can spot, track and identify ballistic missile launches such as the Russian IRBM fired at Ukraine on Thursday - a Cold War system that has been refined over decades into an unblinking global network.

Six Lockheed Martin and Northrop Grumman satellites, known as SBIRS, for space-based infrared system, sit in geostationary orbit around earth hunting for launch signatures, according to the U.S. Space Force, which operates them.