Project Grant 2617823

COLLABORATIVE RESEARCH: GCR: CENTER ON SOLAR WIND-MILKY WAY IMPACTS ON COMPLEX EARTH SYSTEMS (COSMIC) -STUDIES OF EARTH?S PAST HAVE EXPLAINED CYCLES OF CHANGE IN THE PLANET?S CONDITIONS OVER THOUSANDS OF YEARS BUT ARE UNABLE TO UNRAVEL WHAT CAUSES SHIFTS IN EARTH?S ENVIRONMENT OVER MILLIONS OF YEARS. YET, THESE LONGER PATTERNS CAN BE IMPORTANT FOR UNDERSTANDING THE EARTH, THE SOLAR SYSTEM, AND OTHER POTENTIALLY HABITABLE PLANETS. THESE STUDIES HAVE LARGELY IGNORED THE LOCATION OF THE SUN IN THE GALAXY. THE SUN, LIKE OTHER STARS, MOVES THROUGH THE GALAXY AND TRAVERSES MANY DIFFERENT GALACTIC STRUCTURES SUCH AS COLD GALACTIC CLOUDS. RECENT STUDIES INDICATE THAT THE SUN CROSSES COLD GALACTIC CLOUDS MORE OFTEN THAN PREVIOUSLY THOUGHT. THESE CROSSINGS ARE BELIEVED TO SHRINK THE HELIOSPHERE (THE ?COCOON? AROUND THE SOLAR SYSTEM FORMED BY THE SOLAR WIND) AND EXPOSE EARTH TO THE INTERSTELLAR MEDIUM. DURING SUCH PERIODS EARTH WOULD HAVE BEEN EXPOSED TO INCREASED RADIATION AND LARGE AMOUNTS OF HYDROGEN, POTENTIALLY ALTERING EARTH?S ATMOSPHERE IN WAYS THAT AFFECTED TEMPERATURE AND OTHER ELEMENTS OF THE EARTH SYSTEM. THIS PROJECT WILL DETERMINE HOW THE SUN?S GALACTIC ENVIRONMENT HAS INFLUENCED EARTH?S HISTORY. TO REALIZE ITS VISION, THE PROJECT BRINGS TOGETHER EXPERTS IN ASTRONOMY, HELIOPHYSICS, ATMOSPHERIC SCIENCE, AND PALEOCLIMATE. THE PROJECT WILL ALSO SUPPORT PROFESSIONAL WORKFORCE DEVELOPMENT VIA SKILLS AND COMMUNICATION TRAINING, SUMMER SCHOOLS AND WEBINARS TO INCREASE THE RECRUITMENT, RETENTION, AND CAREER DEVELOPMENT OF EARLY CAREER RESEARCHERS IN STEM WHILE SIMULTANEOUSLY TRAINING THE NEXT GENERATION OF SCIENTISTS TO BE FLUENT IN TEAM-BASED, HIGHLY TRANSDISCIPLINARY CONVERGENT RESEARCH. THE PROJECT WILL MAKE USE OF ASTROPHYSICAL SIMULATIONS AND OBSERVATIONS WITH STATE-OF-THE ART HELIOSPHERIC MODELING AND MODERN WHOLE-ATMOSPHERE SIMULATIONS SPANNING THE UPPER ATMOSPHERE TO THE SURFACE. IT WILL INCORPORATE EXISTING DATA SETS AND DEVELOP NEW COSMOGENIC DATA FROM MARINE SEDIMENTS AND EXCEPTIONALLY OLD ICE RECORDS EXTENDING BACK TO ~7 MILLION YEARS FOR DIRECT OBSERVATIONAL CONSTRAINTS ON EARTH?S RADIATION AND ITS IMPACTS DURING THESE EPOCHS. TREATING THE COMBINED GALAXY?SUN?HELIOSPHERE?EARTH SYSTEM AS A COUPLED SYSTEM OPERATING ACROSS VAST SPATIAL AND TEMPORAL SCALES WILL DEMONSTRATE IF AND HOW THE SUN?S ENCOUNTERS WITH INTERSTELLAR COLD CLOUDS ACT AS A FUNDAMENTAL EXTERNAL DRIVER OF EARTH HISTORY. THE BROADER IMPACT WILL EXTEND TO SEVERAL FIELDS OF RESEARCH INCLUDING THE HABITABILITY OF EARTH-LIKE PLANETS. BY ADVANCING FUNDAMENTAL KNOWLEDGE, THIS PROJECT PROMOTES THE PROGRESS OF SCIENCE AND STRENGTHENS THE NATION?S SCIENTIFIC WORKFORCE, SUPPORTING LONG-TERM U.S. PROSPERITY AND INNOVATION. THIS AWARD REFLECTS NSF'S STATUTORY MISSION AND HAS BEEN DEEMED WORTHY OF SUPPORT THROUGH EVALUATION USING THE FOUNDATION'S INTELLECTUAL MERIT AND BROADER IMPACTS REVIEW CRITERIA.- SUBAWARDS ARE NOT PLANNED FOR THIS AWARD.