NASA has selected Rocket Lab to provide the launch service for both the agency’s PolSIR (Polarized Submillimeter Ice-cloud Radiometer) and Total and Spectral Solar Irradiance Sensor-2 (TSIS-2) missions.The two selections are part of NASA’s Venture-Class Acquisition of Dedicated and Rideshare (VADR) launch services contract. This contract allows the agency to award fixed-price indefinite-delivery/indefinite-quantity launch service task orders during VADR’s 10-year ordering period, with a maximum total contract value of $300 million.The PoISIR mission will help provide a better understanding of ice clouds that form at high altitudes throughout tropical and subtropical regions. Rocket Lab will launch PolSIR aboard two of its dedicated Electron rockets no earlier than June 2027 from Launch Complex 1 in Mahia, New Zealand.Consisting of two small satellites, both of PoISIR’s 16U CubeSats have a scientific instrument designed to measure a specific spectrum of electromagnetic radiation, which will determine how the amount of ice in tropical clouds rises and falls during the day, as well as how the ice changes connect to larger storms. The instruments also will help determine how ice clouds affect sunlight and heat radiation throughout the day. The pair of CubeSats will fly in orbits separated by several hours to observe the pattern of cloud ice content changes over a day. This information will help researchers make more accurate weather predictions.The PolSIR mission’s principal investigator is Vanderbilt University in Nashville. Science operations will be conducted by the Space Science and Engineering Center at the University of Wisconsin in Madison. The two spacecraft are being built by Blue Canyon Technologies.The TSIS-2 mission will measure the Sun’s energy input to Earth. The spacecraft will provide critical data for understanding our planet’s ocean currents, seasons, and weather. The mission will continue NASA’s work to study and protect our home planet by providing insights that can only be gathered from space. Rocket Lab will launch TSIS-2 aboard an Electron rocket in early 2027 from Launch Complex 1 in Mahia.The satellite measures Earth’s solar energy input, both the total irradiance, which is the Sun’s overall brightness at the top of Earth’s atmosphere, and the spectral irradiance, or how that energy is distributed across ultraviolet, visible, and infrared wavelengths. The satellite’s two instruments, the Total Irradiance Monitor and the Spectral Irradiance Monitor, are similar to those used for TSIS-1. Together, they cover a wavelength range that includes 96% of the energy in the solar spectrum. While TSIS‑1 works from the International Space Station, TSIS‑2 will operate from a free‑flying spacecraft.Managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland, TSIS-2 includes instruments provided by the Laboratory for Atmospheric and Space Physics at the University of Colorado, Boulder, and the spacecraft is provided by General Atomics – Electromagnetic Systems.NASA’s Launch Services Program, based at the agency’s Kennedy Space Center in Florida, manages the VADR contract.Learn more about VADR online:https://www.nasa.gov/vadr-venture-class-acquisition-of-dedicated-and-rideshare-launch-services