Observing and Modeling the Sun-Earth System

Coronal mass ejections (CMEs) are large eruptions of plasma from the Sun that can affect space weather near Earth. Coronagraphs observe these eruptions by measuring sunlight scattered by electrons in the solar corona and heliosphere. However, these images are two-dimensional projections of a three-dimensional structure, which makes it difficult to determine the true shape, density, and motion of a CME. We introduce SuNeRF-CME, a new method for reconstructing the three-dimensional plasma structure of CMEs from coronagraph images taken from multiple viewpoints.

Solar physicists use instruments called polarimeters to measure the polarization of sunlight, which reveals the strength and structure of the Sun's magnetic field. Before a polarimeter can deliver reliable measurements, it must be calibrated by feeding known polarization states into the instrument. Calibration takes time, and telescope time is precious — particularly for solar telescopes, where intense sunlight limits how long calibration optics can safely remain in the beam. This raises a key question: what sequence of calibration measurements yields the most accurate result in a given amount of time?

The large-scale traveling ionospheric disturbances (LSTIDs) over the Asian-Pacific sector during the 10-11 May 2024 superstorm are investigated using ionosonde observation and simulation from a whole geospace model - Multiscale Atmosphere Geospace Environment (MAGE), which fully couples multiple magnetosphere, ionosphere and thermosphere models.