India's Aditya-L1 and Europe's Proba-3 make historic joint solar discovery

Landmark joint observation of solar eruptions

India's flagship solar observatory, Aditya-L1, and the European Space Agency's Proba-3 mission have jointly observed early-stage coronal mass ejections for the first time. The landmark effort captured the inner workings of solar eruptions close to the Sun's surface, highlighting India's expanding role in global space exploration and scientific research.

Findings from the joint observations, carried out between July and December 2025, have been published in the journal Astronomy & Astrophysics. By combining readings from two different locations in space, scientists measured the mass, density, and thermal energy of these massive solar eruptions with unprecedented precision.

How Aditya-L1 and Proba-3 mapped the Sun's corona

Coronal mass ejections release huge clouds of charged plasma into outer space. When directed towards Earth, intense bursts can disrupt electrical power grids, cripple satellite communications, affect GPS signals, and pose risks to spacecraft in low Earth orbit. Capturing these eruptions right after they form has historically been difficult because the solar disk blinds standard space telescopes.

India's Aditya-L1 spacecraft, positioned at the first Earth-Sun Lagrange Point roughly one million miles away, used its Visible Emission Line Coronagraph (VELC) payload. VELC splits coronal light into distinct wavelengths through spectroscopy, providing precise data on gas density and thermal energy.

At the same time, Europe's Proba-3 mission operated in a highly elliptical Earth orbit. Using twin spacecraft flying in tight formation to create artificial solar eclipses, Proba-3 deployed its ASPIICS coronagraph to capture high-resolution imagery showing the physical shape, dynamics, and overall mass of the eruptions.

Comparing the solar eruption events

The Indian Space Research Organisation (ISRO) noted that combining an imaging coronagraph with a spectroscopic instrument provides a far more complete view of how solar storms originate. The fast-moving eruption on 14 September carried only a tiny fraction of its total energy as heat, whereas the slower event on 16 September expanded rapidly near the solar surface, causing its thermal energy to match its kinetic energy.

Strengthening global scientific leadership

ISRO said the collaborative research demonstrates the immense potential of combining complementary space instruments to set new constraints on solar models. The achievement reinforces India's position as an indispensable partner in global space science, proving the advanced technical precision of indigenous payloads like VELC operating alongside international missions.