PUNCH Passes System Requirements & Mission Design Review
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.
"For over 50 years, we've studied the solar corona by remote imaging and the solar wind by
direct sampling," said PUNCH Principal Investigator Dr. Craig DeForest of SwRI's Space Science and Engineering
Division. "PUNCH will bridge that gap by imaging the solar wind itself as it leaves the outermost reaches of
the Sun's corona." The solar wind, a supersonic stream of charged particles emitted by the Sun, fills the heliosphere, the bubble-like region of space encompassing our solar system. Its boundary, where the interstellar medium and solar wind pressures balance, ends the sphere of the Sun's influence.