On April 8, 2020, the Polarimeter to UNify the Corona and Heliosphere (PUNCH) mission achieved an important milestone, passing NASA’s critical System Requirements Review/Mission Definition Review (SRR/MDR). Southwest Research Institute is leading PUNCH, a NASA Small Explorer (SMEX) mission that will integrate understanding of the Sun’s corona, the outer atmosphere visible during eclipses, with the tenuous “solar wind” filling the solar system.
Source:
https://phys.org/news/2020-04-mission-milestone.html