Ahead of August’s solar eclipse, The Innovation Platform spoke with experts from the European Space Agency about the significance of eclipses in advancing solar research and the opportunity to observe, study and understand our Sun
A total solar eclipse took place on the 12th of August 2026, visible across parts of Europe and the North Atlantic.
The European Space Agency (ESA) made the most of this opportunity by hosting a range of activities to educate and engage the public about eclipses, including live broadcasts by renowned experts and a large public event that brought enthusiasts together in León.
Total solar eclipses, in which the Moon completely obscures the Sun, present a rare and significant opportunity to observe the solar corona and other phenomena related to solar activity. While the public observed, ESA and its solar missions used the opportunity to collect more data and enhance our understanding of the Sun’s dynamics.
In advance of the eclipse, The Innovation Platform spoke with experts from the European Space Agency about the organisation’s initiatives and activities as well as the broader significance of such events in advancing solar research.
Can you provide a brief introduction to the total solar eclipse happening in August, along with ESA’s programme to cover it?
For ESA, this event represents not only a spectacular public engagement moment but also a unique opportunity to bring together millions of people looking up at the sky at the same time, reflecting on their place in the Universe.
ESA’s programme will include live broadcast coverage from the Astrophysical Observatory of Javalambre in Teruel, Spain, featuring ESA’s Director of Science, Prof Carole Mundell, alongside experts from our missions providing scientific insight and context. The programme will be hosted by the internationally renowned science communicator Dame Dr Maggie Aderin.
In parallel, a large-scale public event will be organised in León, offering thousands of people the opportunity to gather, observe the eclipse, and celebrate this remarkable phenomenon, while discovering ESA’s missions and activities in an engaging and accessible way.
To know more about the two activities, please access here.
An education kit has also been developed in both Spanish and English by the CESAR education project, including a set of easy-to-perform experiments designed to help audiences explore and better understand the science behind solar eclipses.
Why are total solar eclipses significant for scientific research?
Eclipses are one way of observing the solar corona, the outer layer of the solar atmosphere. This is a very hot and dynamic layer where most of the solar activity takes place. However, it is very difficult to observe due to its very low density and coronal light emission that is many orders of magnitude fainter than the light from the solar surface and that gets filtered by the Earth’s atmosphere (extreme ultraviolet, X-rays, …). Only during eclipses is the bright light of the solar disk covered by the moon, and we can observe the corona in white light scattered by the coronal material.
Observations from space offer a different view of the same region, as solar telescopes on board ESA missions like SOHO, Solar Orbiter, and Proba-2 can observe the EUV and X-rays directly. Most scientific opportunities these days lie in the combination of data from all these observatories. The sun and its activity are affecting a very large region of space around it (called the heliosphere), and only by combining data taken from different viewpoints and in different wavelengths and resolutions can we understand the effect it has on our own planet Earth.
What unique opportunities do they provide for studying the Sun?
Eclipses as viewed from Earth are still a vital component in this. The moon offers a close-to-perfect blockage of the solar disk, which offers a unique view of the complex solar corona close to the disk. This is very difficult to achieve in space. The closest we can get to an eclipse is through the recently launched ESA Proba-3 mission that is using precise formation flying to create artificial solar eclipses in space.
Beyond solar science, eclipses also act as natural laboratories for studying Earth’s atmosphere, as the sudden drop in sunlight affects temperature, winds, and the ionosphere.
In addition, total solar eclipses offer unique experimental conditions which enable precise tests of fundamental physics, for example, the confirmation of Einstein’s general relativity.
Together, these factors make total solar eclipses invaluable events that provide insights into the Sun–Earth system and processes that cannot be replicated under normal observational conditions.
What instruments or technology are used to collect data during a total solar eclipse?
During a total solar eclipse, scientists use a combination of advanced instruments to capture detailed data about the Sun and its effects on Earth. Ground-based optical telescopes equipped with high-resolution, high-speed cameras image the faint solar corona, while spectrographs and spectrometers analyse its light to determine composition, temperature, density, and motion.
Polarimeters measure the polarisation of coronal light to infer magnetic field structures, and radio and infrared instruments allow observations of plasma processes and spectral lines not visible in optical wavelengths.
At the same time, satellites such as SOHO or Solar Orbiter provide continuous complementary observations across ultraviolet and X-ray wavelengths, helping place eclipse data in a broader context.
In particular, Solar Orbiter is planning a dedicated set of Metis-led observations (the mission’s coronograph), complemented by coordinated measurements from the other remote-sensing instruments (PHI, SPICE, and EUI). Data from PHI will be used in collaboration with the US-based PSI group to generate predictive models of the solar corona. These activities are expected to begin approximately three weeks in advance and will be continuously refined as new PHI data becomes available.
The Solar Orbiter, Proba 3, and SMILE missions are all studying the Sun and its effects. Can you provide an overview of these missions and the specific objectives ESA aims to achieve during the solar eclipse?
For an overview of those three missions, please consult here: Solar Orbiter, Smile and Proba 3.
ESA is coordinating the observations of all its solar missions, including Solar Orbiter, SOHO and Proba-3, to create a unique dataset during the upcoming eclipse that can be combined with the eclipse data from Earth and the observatories both on the ground and in space of our collaborative partners.
On 12 August, during the solar eclipse, Solar Orbiter will be very close to the Sun, at a third of the Earth-Sun distance and in quadrature with Earth. This means it will be observing the Sun ‘from the side’, allowing scientists to place the complex coronal structures as seen from Earth in a 3D view.
If a solar eruption is observed leaving the Sun towards the west, Solar Orbiter will be able to measure its characteristics when it reaches the satellite. Or vice versa, if Solar Orbiter watches a solar eruption towards Earth, we’ll be able to better predict the impact it will have on our planet.
At the same time, Proba-3 will make coronal observations from Earth’s point of view but in complementary wavelengths. This will allow us to understand the temperatures and dynamic variations in the corona at the time of the eclipse.
How have any specific past experiences or findings from previous eclipses influenced current research priorities?
Past total solar eclipses have had a profound influence on current research priorities. One of the most famous examples is the 1919 eclipse, which provided the first experimental confirmation of Einstein’s general relativity, demonstrating how eclipses can be used to test fundamental physics under extreme conditions.
Later eclipses led to the discovery of helium in the solar spectrum and highlighted the unexpectedly high temperatures of the corona, establishing long-standing questions such as the coronal heating problem that remain central to solar physics today. Observations over successive eclipses have also shown how coronal structures change with the solar cycle, prompting ongoing research into the role of magnetic fields in driving solar activity and space weather.
More recently, eclipse campaigns have demonstrated the value of combining ground-based measurements with satellite observations, revealing fine-scale structures in the inner corona that are difficult to capture with space-based coronagraphs alone. These findings have directly influenced the design of modern missions like Proba-3, as well as current priorities such as improving space weather forecasting.
Are there any challenges or limitations you anticipate when observing the solar eclipse? If so, how will these be addressed?
A key challenge for the 12 August eclipse is that it will take place close to sunset, meaning the Sun will be positioned very low on the horizon. This significantly increases the risk of the view being obstructed by local terrain, buildings, or atmospheric haze and can also affect the clarity and quality of observations. Careful selection of the observation site is critical, ensuring a complete line of sight towards the western horizon.
To address this, ESA has chosen to broadcast from a high-altitude site at around 2,000 metres above sea level, such as the Astrophysical Observatory of Javalambre. Observing from an elevation not only reduces the likelihood of obstructions but also improves atmospheric conditions, minimising distortion and light scattering near the horizon. This strategic choice maximises the chances of capturing the eclipse under the best possible conditions for high-quality live broadcasting.
In addition, we have partnered with the Astrophysical Institute of Andalusia and the Stars4All Foundation. This collaboration provides an important layer of flexibility to our observation strategy, as the expert team will be deployed at a separate location with the capability to relocate if weather conditions are not favourable. By maintaining a mobile setup, they can actively track clearer skies along the eclipse path, significantly increasing the chances of securing high-quality observations.
Looking towards future eclipses, what long-term research goals does ESA have regarding solar research?
The ultimate goal of most of the current and future solar physics research is to understand the physics of stars, and the Sun in particular, and to understand the influence it has on its surroundings, including all planets in our solar system.
ESA’s current focus in solar research is driven by the Solar Orbiter mission, which, for the first time, is observing solar activity from much closer distances (up to within Mercury’s orbit) and from outside the ecliptic plane. It links the high-resolution observations taken by its telescopes with the measurements acquired by the solar wind sensors on the probe, to link cause to effect and better model the impact solar activity will have on the Earth.
Nonetheless, the biggest strength is the coordination of its observations with those of other solar observatories on the surface and around the Earth and elsewhere in the heliosphere to get a better sense of the Sun’s influence on the whole heliosphere.
Some examples include: Coordinated campaigns are set up with other space missions that have either complementary instruments or provide a 3D view of the complex structures we are observing in the solar wind. We collaborate with the NASA mission Solar Probe, which orbits even closer to our star but only with in situ sensors; hence, it is effectively ‘blind’ to the activity originating on the Sun.
Ground observatories like the Swedish Solar Telescope and DKIST provide more details on solar source regions, of which Solar Orbiter provides both a 3D view and a wider context.
How does ESA plan to incorporate the data from this eclipse into future missions or projects?
Current and future advances in solar physics are driven by the combination of data from all the observatories we have on the ground and in space, including solar eclipses. Solar Orbiter is providing us, for the first time, with imagery data from very close to the Sun and has provided new insights into solar phenomena we could not observe earlier (e.g. very small-scale solar flares, magnetic ’switch-backs’ in the early solar wind, identification of the source and acceleration mechanisms for the solar wind, etc.). The mission has recently started its high-latitude phase in which the satellite’s orbit moves out of the ecliptic plane, allowing for observations of both solar poles. These are currently still blind spots and contain crucial information on the magnetic cycle of the Sun that lies at the basis of its 11-year-long activity cycle.
Fundamental solar physics, as done with ESA’s current missions, is crucial to eventually being able to forecast the impact of solar and space weather on our planet, infrastructure and ourselves. Space weather modelling and forecasting have been developing over the last 30 years only, and we are still far from reliable forecasts that are fast enough to react on Earth. One of ESA’s future missions, Vigil, is designed to help reach that goal. ESA Vigil will be placed in Lagrange point 5, located at a similar distance from the Sun as Earth, but at an angle of 60 degrees with Earth. It will provide early warnings of solar storms, including solar flares and coronal mass ejections, with forecasts up to 4 to 5 days ahead. It will be a mission fully dedicated to the operational service of space weather monitoring.
The solar data being acquired now and in the coming years, from the unique viewpoints of Solar Orbiter combined with other assets, including the solar eclipse data, will all feed into the preparation for Vigil.
The upcoming eclipse of 2027 will also offer a unique opportunity for scientific research as it will cross the African continent and allow several-minute-long totality observations over a very wide stretch of land. This allows for observing the solar coronal dynamics while the eclipse passes over the continent.
