General Atomics Electromagnetic Systems (GA-EMS) has successfully integrated the scientific payload for NASA’s Total and Spectral Solar Irradiance Sensor-2 (TSIS-2) mission onto its dedicated GA-150 satellite. This critical milestone advances the mission toward extending the decades-long, continuous record of solar irradiance data, which is vital for understanding the Sun’s influence on Earth’s climate and atmosphere.
The integration work, performed at GA-EMS’s facility in Centennial, Colorado, included precise instrument alignment and performance checkouts. Following these achievements, NASA has granted the project an Authority to Operate under its risk management framework. A comprehensive spacecraft test is now planned to verify end-to-end system performance ahead of the mission timeline.
TSIS-2 will operate differently from its predecessor, TSIS-1, which is stationed on the International Space Station. By flying as a standalone mission on the dedicated GA-150 satellite in a sun-synchronous orbit, TSIS-2 is designed to collect an uninterrupted stream of high-quality data.
The mission’s dual-instrument payload was developed by the University of Colorado Boulder’s Laboratory for Atmospheric and Space Physics (LASP) under a separate NASA contract. It consists of a Total Irradiance Monitor (TIM) and a Spectral Irradiance Monitor (SIM). These sensors will measure the Sun’s total energy output and its distribution across wavelengths, providing data crucial for studying Earth’s ozone, atmospheric circulation, and ecosystems.
“Integrating the TSIS-2 payload is a significant milestone,” said Scott Forney, president of GA-EMS. “The dedicated GA-150 platform will help ensure NASA receives the high-quality data this mission is designed to deliver.”
LASP researchers emphasized the mission’s importance in building upon the legacy of TSIS-1, which has provided highly accurate measurements since 2017. “The TSIS-2 mission will allow our team to continue to improve this essential continuous solar data record,” said Erik Richard, Ph.D., principal investigator at LASP. The goal is to extend this irreplaceable climate data series with unprecedented accuracy for the global scientific community.
