The 2026 Total Solar Eclipse: A Complete Guide to the International Science Campaign

On August 12, 2026, a total solar eclipse will sweep across Greenland, Iceland, and northern Spain — the first total eclipse visible from Europe since 1999 . With maximum totality lasting just 2 minutes and 18 seconds off the coast of Iceland , an unprecedented international science campaign will deploy high-altitude aircraft, dozens of balloons, space-based observatories, and ground stations to extract as much data as possible in that brief window . Here is a detailed breakdown of the instruments, missions, and the key questions they aim to answer.

NASA's WB-57 Jet: Chasing the Shadow from the Stratosphere

A NASA-funded science team will chase the Moon's shadow using a WB-57 high-altitude research aircraft . The jet will fly at approximately 50,000 feet (15 km) in the stratosphere, above most clouds and atmospheric distortion, allowing its instruments to capture the clearest views of the eclipse .

Mounted in the nose cone is the SCIFLI Multispectral Airborne Imager (SAMI), a system of four cameras that take high-resolution images at least 20 frames per second across visible and infrared wavelengths . By flying at 460 mph (740 km/h) along the path of totality, the jet will extend its observation of the corona to nearly three minutes — about 30 seconds longer than ground-based observers . The altitude also allows the cameras to observe some infrared wavelengths that are absorbed by the lower atmosphere before reaching the ground .

NASA is deploying three WB-57 aircraft for this campaign . The planes will be joined in the air by the Irish Air Corps and several small private planes also vying for optimal viewing positions .

The Balloon Campaign: 80+ Sensors Probing the Atmosphere

The NASA-supported Nationwide Eclipse Ballooning Project (NEBP) will send five university student teams to Iceland and Spain to launch scientific balloons before, during, and after the eclipse . Led by Dr. Angela Des Jardins at Montana State University, the teams plan to launch roughly 80–86 balloons overall .

• In Iceland, the two Atmospheric Science teams will launch about 80 small radiosondes over a 30-hour campaign, starting 18 hours before the eclipse and continuing for eight hours afterward . These balloons carry sensors to measure temperature, pressure, humidity, and wind in the atmospheric boundary layer — the lowest part of the atmosphere where weather happens .
• In Spain, three Engineering teams will launch six larger latex balloons carrying payloads of up to 6 kg each . These will capture 360-degree imagery of the eclipse shadow from a near-space perspective and measure ozone levels .

ESA Solar Orbiter and Proba-3: Coordinated Space-Based Observations

ESA's Solar Orbiter spacecraft will enter a dedicated Remote-Sensing Window (RSW) starting August 9, 2026, enabling coordinated observations with the eclipse ground campaigns . Its remote-sensing instruments — EUI, PHI, Metis, and SPICE — will image the Sun's atmosphere, with special attention on August 12 .

Solar Orbiter's unique vantage point on the solar far side in the weeks leading up to the eclipse means it can map magnetic fields on the side of the Sun not visible from Earth, compiling — together with Earth-orbiting probes — a complete picture of the Sun's magnetic activity . The spacecraft's data will be cross-referenced with ground-based and airborne eclipse measurements to study the corona's structure and the solar wind's origin .

ESA's Proba-3 mission, carrying the ASPIICS coronagraph, has been in a continuous set of coronagraphy orbits since July 28, 2026, and will observe before and after the ground eclipse on August 12 . ESA is running daily simulations of the eclipse at sun.esa.int/eclipse to coordinate predictions with both Solar Orbiter and Proba-3 .

Ground Stations: Ebre Observatory and Beyond

The historic Ebre Observatory (Observatori de l'Ebre) in Roquetes, Spain — located within the path of totality — will conduct ground-based solar and atmospheric measurements. Its instruments will capture coronal emission lines, magnetic field changes, and ionospheric disturbances during totality, complementing the airborne and space-based platforms.

Other ground stations across Spain, including sites coordinated by the Spanish National Geographic Institute (IGN), will time the eclipse contacts and monitor ionospheric conditions .

The Four Key Science Questions

1. What heats the Sun's corona to millions of degrees? The Sun's outer atmosphere is hundreds of times hotter than its surface, something that defies simple physics. The WB-57's SAMI imager will capture high-resolution, multi-spectral images of the corona's fine structure and temperature gradients . Comparing these with Solar Orbiter's simultaneous remote-sensing data will help test models of coronal heating mechanisms .

2. How does the solar wind propagate from the Sun? Coordinated observations between ground-based coronagraphs, the WB-57, Solar Orbiter, and Proba-3's ASPIICS coronagraph will track plasma flows from the low corona out into the solar wind . The eclipse provides a rare natural occultation that reveals the corona's faintest regions, where the solar wind is accelerated.

3. What are the atmospheric impacts of a sudden solar shadow? The balloon campaign will measure how surface temperatures drop, winds shift, and planetary boundary layer turbulence changes when sunlight is abruptly blocked . These data will improve models of how solar radiation drives weather and boundary-layer dynamics.

4. How does the ionosphere respond to rapid solar flux changes? The Ebre Observatory and other ground stations will track ionospheric electron density and magnetic field variations during totality, probing the coupling between solar radiation and Earth's upper atmosphere.

How to Watch and Follow Along

NASA will stream the eclipse live starting at 1:15 p.m. EDT on August 12, 2026, on NASA.gov/live . ESA is providing daily simulation updates at sun.esa.int/eclipse and coordination resources at esa.int/solareclipse .

For viewers across Europe, northern North America, and western Africa, a partial solar eclipse will be visible — in many locations more than 90% of the Sun will be covered .