Polarimeter to Unify the Corona and Heliosphere (PUNCH)
Craig DeForest, Sarah Gibson, Ronnie Killough, Nick Waltham, Matt Beasley, Robin Colaninno, Glenn Laurent, Daniel Seaton, Marcus Hughes, Madhulika Guhathakurta, Nicholeen Viall, Raphael Attie, Dipankar Banerjee, Luke Barnar, Doug Biesecker, Mario Bisi, Volker Bothmer, Antonina Brody, Joan Burkepile, Iver Cairns, Jennifer Campbell, david Cheney, Traci Case, Amir Caspi, Rohit Chhiber, Matthew Clapp, Steven Cranmer, Jackie Davies, Curt de Koning, Mihir Desai, Heather Elliott, Samaiyah Farid, Bea Gallardo-Lacourt, Chris Gilly, Caden Gobat, Mary Hanson, Richard Harrison, Donald Hassler, Chase Henley, Alan Henry, Russell Howard, Bernard Jackson, Samuel Jones, Don Kolinski, Derek Lamb, Florine Lehtinen, Chris Lowder, Anna Malanushenko, William Matthaeus, David McComas, Jacob McGee, Huw Morgan, Divya Oberoi, Dusan Odstrcil, Chris Parmenter, Ritesh Patel, Francesco Pecora, Steve Persyn, Victor Pizzo, Simon Plunkett, Elena Provornikova, Nour Eddine Raouafi, Jillian Redfern, Alexis Rouillard, Kelly Smith, Keith Smith, Zachary Talpas, James Tappin, Arnaud Thernisien, Barbara Thompson, Samuel Van Kooten, Kevin Walsh, David Webb, William Wells, Matthew West, Zachary Wiens, Yan Yang
公開日: 2025/9/18
Abstract
The Polarimeter to Unify the Corona and Heliosphere (PUNCH) mission is a NASA Small Explorer to determine the cross-scale processes that unify the solar corona and heliosphere. PUNCH has two science objectives: (1) understand how coronal structures become the ambient solar wind, and (2) understand the dynamic evolution of transient structures, such as coronal mass ejections, in the young solar wind. To address these objectives, PUNCH uses a constellation of four small spacecraft in Sun-synchronous low Earth orbit, to collect linearly polarized images of the K corona and young solar wind. The four spacecraft each carry one visible-light imager in a 1+3 configuration: a single Narrow Field Imager solar coronagraph captures images of the outer corona at all position angles, and at solar elongations from 1.5{\deg} (6 R$_\odot$) to 8{\deg} (32 R$_\odot$); and three separate Wide Field Imager heliospheric imagers together capture views of the entire inner solar system, at solar elongations from 3{\deg} (12 R$_\odot$) to 45{\deg} (180 R$_\odot$) from the Sun. PUNCH images include linear-polarization data, to enable inferring the three-dimensional structure of visible features without stereoscopy. The instruments are matched in wavelength passband, support overlapping instantaneous fields of view, and are operated synchronously, to act as a single ``virtual instrument'' with a 90{\deg} wide field of view, centered on the Sun. PUNCH launched in March of 2025 and began science operations in June of 2025. PUNCH has an open data policy with no proprietary period, and PUNCH Science Team Meetings are open to all.