10/08/2026
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On 12 August 2026, parts of Europe will experience a total solar eclipse. With the Sun’s bright disc covered, its surrounding atmosphere – the solar corona – will become visible to the naked eye. Unfortunately, total solar eclipses are rare and last at most a few minutes, giving scientists little time to study the Sun’s enigmatic halo.
This is why ESA developed missions that create eclipses artificially, and why experts use computer models to create digital simulations. So how do we do it, and why is it important?
In two days, the Moon will completely shield the Sun for parts of Greenland, Iceland, Spain and Portugal, creating a total solar eclipse. For up to just over two minutes, the brightness of day will turn into twilight and reveal the solar corona, normally kept invisible by the Sun’s glare.
The corona is where space weather originates: where the solar wind gains speed before streaming out into the Solar System, and where coronal mass ejections arise. Space weather can disrupt our satellite networks, communication infrastructure, power grids and other technologies that modern society relies on.
Until recently, the full corona could only be observed from Earth during the short periods of total eclipses. These occur around once, very rarely twice a year, in different places across the globe, and last at most a few minutes.
A solar eclipse is an example of a natural ‘solar occultation’ – when an object (in this case the Moon) blocks the Sun’s disc from an observer’s perspective. To stretch the short observation window that natural eclipses offer, scientists invented ways to create occultations artificially, using an instrument called a ‘coronagraph’: a telescope incorporating a disc to occult the Sun.
Total solar eclipse on demand
Most coronagraphs can reliably image the outer part of the corona, but not the region between it and the Sun’s surface. To fill this observation gap, ESA developed and launched its artificial eclipse-maker Proba-3, a mission that consists of a pair of satellites flying 150 metres apart and autonomously operating as a single spacecraft.
The Occulter spacecraft acts as the Moon and eclipses the Sun for the Coronagraph spacecraft, which then uses its scientific instrument, ASPIICS, to capture images of the solar corona for hours at a time.
Andrei Zhukov, principal investigator for the ASPIICS instrument at the Royal Observatory of Belgium, comments on one of the mission’s most recent artificial eclipses: “This is the 62nd eclipse of Proba-3’s nominal operations – a part of the mission during which we acquire coronal images.
“What makes this one unique is that it was taken about two weeks before the upcoming natural eclipse on 12 August. It takes the Sun two weeks to rotate halfway around its axis, so if we mirror the image horizontally, we get a prediction of what the corona will look like during the natural eclipse seen from Earth two days from now. The overall large-scale coronal structure usually doesn’t change much during that time.”
Click here to read more about what Proba-3 is doing for the 2026 total eclipse.
Seeing another side of the Sun
While Proba-3’s mimicry of solar eclipses is unique, other solar missions are taking this eclipse just as seriously. In the days leading up to 12 August, the ESA-led Solar Orbiter mission is running a special observation campaign with its various remote-sensing instruments.
Totality reveals structures in the corona that are shaped by the Sun’s magnetic field. This means that eclipses provide a rare opportunity to test whether computer simulations accurately capture the Sun’s magnetic environment.
“A total solar eclipse lets us verify that our models are correct by comparing forecasts with actual observations,” says Jorge Amaya, ESA Space Weather Modelling Coordinator.
Most solar observations are made from near Earth, providing only a limited view of a vast three-dimensional system. Luckily, Solar Orbiter follows a different path around the Sun than other solar observatories. Today, the spacecraft is facing the side of the Sun that will soon roll into Earth’s view, giving observers on the ground the opportunity to decide which targets to focus on during the eclipse.
Particularly useful are the magnetic maps (magnetograms) of the Sun’s visible surface, recorded by Solar Orbiter’s Polarimetric and Helioseismic Imager (PHI). With the spacecraft’s unique vantage point, these data provide modellers with a much more complete picture of the Sun’s magnetic field today.
For example, PHI is seeing a newly emerging active region on the Sun, which is likely to affect what the corona will look like during the 12 August eclipse. Spotting this active region would not have been possible without Solar Orbiter.
“The magnetic field lines that we see in simulations are like hairs in a fuzz ball,” adds Jorge. “Observing the Sun from multiple viewpoints allows us to determine their orientation in three dimensions. That is the key to dramatically improving forecasts of how solar activity will affect our technology.”
Solar Orbiter’s location today gives us a sneak preview of what ESA’s space weather forecasting mission Vigil will see. Planned for launch in 2031, Vigil will tail Earth to provide continuous, near real-time observations of the Sun’s side.
“With Proba-3 and Solar Orbiter, we have an unprecedented view of our star,” comments Miho Janvier, ESA project scientist for the two missions. “Both missions are contributing to our understanding of the Sun, from its surface to its extended atmosphere. The upcoming total solar eclipse offers a chance to see how this knowledge comes together, comparing observations with modelling.”
Virtual totality
ESA’s Solar Orbiter team is providing their unique data to Predictive Science Inc. to accurately predict what the Sun’s corona will look like during the upcoming total solar eclipse. You can see the latest predictions at https://eclipse.predsci.com/#current-prediction
In parallel, KU Leuven is supporting ESA’s Space Weather Office with predictions of what we’ll see during the 12 August eclipse: Read more about KU Leuven’s predictions.
Eclipse livestream
If you are unable to watch the full eclipse in person, tune in to ESA’s live broadcast on 12 August at 19:30–20:45 CEST. Here’s how to watch the broadcast.
Important: Looking directly at the Sun without proper protection can cause serious eye damage. Regular sunglasses are not safe for observing a solar eclipse. To watch the eclipse safely, always use certified eclipse glasses that meet the appropriate safety standards and wear them at all times during the partial phases. Only during totality – when the Moon completely covers the Sun – is it safe to briefly look without protection. As soon as the Sun begins to reappear, eclipse glasses must be worn again. Read more about how to observe a solar eclipse safely.