A solar eruption is often drawn as a bubble expanding neatly away from the Sun. New research involving India's Aditya-L1 observatory shows why that picture can be misleading. Scientists studying a coronal mass ejection, or CME, found that the eruption expanded at different rates in different directions. The uneven shape matters because a CME's geometry can influence how it moves through space and, eventually, how accurately its arrival near Earth can be estimated.

What the researchers measured

The Indian Institute of Astrophysics team combined observations from the Visible Emission Line Coronagraph, known as VELC, aboard Aditya-L1 with images from NASA's Solar Dynamics Observatory. The eruption occurred on 5 August 2024; the findings were described in an Astrophysical Journal Letters study highlighted by India's Department of Science and Technology on 3 November 2026. VELC recorded light from hot plasma in the Sun's corona. Changes in that light's wavelength helped reveal material moving both toward and away from the observer.

The team then tested a three-dimensional model of the eruption. According to the government research summary, a symmetric model could not reproduce the observed spectral pattern, while an inclined, unevenly expanding model came much closer. This is a specific result for the event studied. More observations are needed before the method's usefulness across different types of eruptions can be judged.

Why shape matters for space weather

Large solar eruptions can disturb the space environment in which satellites and communication systems operate. Forecasting depends in part on estimating an eruption's direction, speed and interaction with the solar wind. If a CME expands unevenly, a simple round-bubble assumption may miss features that affect its path and timing. The researchers say their combined imaging and spectroscopy approach could help reconstruct motion in the lower corona, where changes happen quickly and a single camera view has limits.

For India's space programme, the result illustrates the value of Aditya-L1 as a research platform. It does not mean a new warning service has launched or that disruption from this historic eruption is expected now. The practical next step is to apply the technique to more events and compare its estimates with later observations. Read the Department of Science and Technology announcement and the research paper.