Firefly: The Case for a Holistic Understanding of the Global Structure and Dynamics of the Sun and the Heliosphere

This white paper presents the current knowledge gaps in understanding how magnetic fields
control solar (and by extension, stellar) activity in timescales from minutes to years and discusses
a transformative observational approach to fill those gaps. The solar activity drives space weather
as the result of dynamic magnetic fields forming in the solar interior and evolving continuously
until reaching levels of complexity in the atmosphere that trigger eruptions. However, we do not
fully understand how solar and, more generally, stellar magnetic fields are generated and how they
evolve through the eruptive states.

The major obstacle is our reliance on observations from a single viewpoint, particularly in the
ecliptic plane. This vantage point can only provide limited information for (i) understanding the
generation of solar magnetic fields deep in the convection zone; (ii) determining the origin of the
solar cycle and predicting its timing and strength; (iii) explaining the causes of solar activity and
their triggers; (iv) reliably predicting when and how CMEs will impact Earth and other planets; (v)
fathoming the structure and dynamics of the corona as it creates the heliosphere; (vi) understanding the energization and transport of energetic particles; etc.