Indian and European solar observatories jointly study coronal mass ejections in a first

Key facts

• Scientists at the Indian Institute of Astrophysics (IIA) in Bengaluru, with international collaborators, for the first time analysed coronal mass ejections (CMEs) using joint data from India's Aditya-L1 mission and Europe's Proba-3 mission.
• The Visible Emission Line Coronagraph (VELC) on Aditya-L1 provided spectroscopic observations, while the ASPIICS payload on Proba-3 provided imaging observations of nearly the same part of the low solar corona.
• Only two CMEs, on September 14 and 16, 2025, were simultaneously recorded by VELC and ASPIICS from July to December 2025; the September 14 CME was fast at about 645 km/s, while the September 16 CME was slower at 145 km/s.
• Mass and thermal energy estimates from the two instruments agreed well; in the September 14 CME thermal energy was only about 1% of the total, while in the September 16 CME thermal energy grew to match kinetic energy, with magnetic energy comparable to or greater than kinetic energy.
• Aditya-L1, India's first dedicated solar mission, was launched by PSLV-C57 on September 2, 2023, and ESA's Proba-3 was launched by PSLV-XL from Sriharikota on December 5, 2024.
• Proba-3 consists of two spacecraft about 150 metres apart, with one casting a shadow on the other.