Parker Solar Probe 23rd Perihelion (March 21 - 25, 2025)
If you have observational results for this campaign, please contact us at whpi_help@hao.ucar.edu
New page with information, description, and links to maps
Next colloquium: TBD
See Colloqiua Page for recordings of past presentations.
Next Show & Tell: TBD
See Show & Tell Page for recordings of past tutorials.
The Whole Heliosphere and Planetary Interactions (WHPI) is an international initiative initially focused around solar minimum and has now expanded to all phases of the solar cycle, with the main aim of understanding the interconnected sun-heliospheric-planetary system and how the solar magnetic and radiative output propagates through the heliosphere and affects the Earth and planets' atmospheres and magnetospheres. The role of WHPI has been to facilitate and encourage interdisciplinary activities through coordinated observing campaigns, dedicated workshops, and colloquia, where observers, modelers, and interested researchers get together to discuss, compare, and combine research results.
The international Whole Sun Month (WSM; 1996, special journal issue) and Whole Heliosphere Interval (WHI; 2008, special journal issue) were coordinated observing and modeling efforts to characterize the three-dimensional, interconnected solar-heliospheric systems during solar minimum. By focusing on particular solar rotations near solar minimum, specific structures and activity could be traced throughout the heliosphere and down into the Earth's space environment and upper atmosphere.
The intervals have extended their discipline range with each iteration: from Sun-solar wind (WSM) to Sun-solar-wind-geospace (WHI). It was thus appropriate to broaden the emphasis further to include planetary magnetospheres and atmospheres and, in particular, planetary space weather. As such, the Whole Heliosphere and Planetary Interactions (WHPI) emerged (See summary poster). With an unprecedented range of ground-based and space-based instruments deployed, including the exciting new Parker Solar Probe (PSP), the time was ripe for this third focus period. The simpler magnetic configuration and infrequency of Coronal Mass Ejections (CMEs) made solar minimum an ideal time to follow how the solar magnetic and radiative output propagate through the heliosphere and affect the Earth and planets' atmospheres and magnetospheres. Results of the minima comparison were published in an AGU Journal Special Issue.
As activity picked up with the onset of Solar Cycle 25 (solar cycle progression), WHPI grew beyond the solar minima and continued to support sun-heliospheric-planetary science through dedicated campaigns, colloquia, and workshops. The campaigns focus on specific periods, such as PSP perihelions, the 2024 Total Solar Eclipse, and a special campaign for comet C/2024 S1 (ATLAS) observations, which are a great opportunity for coordinated observations and testing of models and predictions. However, we emphasize that WHPI science is not limited to these time periods, and we welcome feedback and suggestions from the community as we plan future campaigns and activities.
All interested parties are encouraged to sign up for the WHPI mailing list, and visit this WHPI web page for further information. Listings of upcoming/past colloqiua and other WHPI-related events can be found on our Participate page.
Join us in creating a "third data point", as we chart our star's influence across the millennia!
