NASA’s newest mission, TRACERS, soon will begin studying how Earth’s magnetic shield protects our planet from the effects of space weather. Short for Tandem Reconnection and Cusp Electrodynamics Reconnaissance Satellites, the twin TRACERS spacecraft lifted off at 11:13 a.m. PDT (2:13 p.m. EDT) on Wednesday, July 23, 2025, aboard a SpaceX Falcon 9 rocket from Space Launch Complex 4 East at Vandenberg Space Force Base in California.

The journal Space Science Reviews is publishing a collection of articles about the University of Iowa-led Tandem Reconnection And Cusp Electrodynamics Reconnaissance Satellites (TRACERS) mission. This collection presents the science objectives of the mission, descriptions of the design and calibration of the plasma instruments, and other important aspects of the mission.