A total solar eclipse will create a celestial spectacle across parts of Greenland, Iceland, northern Spain, and northeastern Portugal on Wednesday, August 12, marking the first time in more than two years that the phenomenon has occurred on Earth.
The event will see the Moon pass directly between the Sun and Earth, completely blocking sunlight in select areas along a path of totality and casting a momentary darkness over the land.
According to the National Aeronautics and Space Administration, a total solar eclipse occurs when the Moon passes between the Sun and Earth, projecting a shadow over the planet that completely blocks solar light in certain areas.
While totality will be restricted to a narrow corridor, a partial solar eclipse, in which only a portion of the sun's light is blocked, will be visible across broader regions of Europe, Africa, and North America.
The event marks the first total solar eclipse visible in continental Europe since 2006, according to the European Space Agency. Although a total solar eclipse crossed Mexico, the United States, and Canada in April 2024, continental Spain has not witnessed a total solar eclipse since 1905. The upcoming August event is the first of three total solar eclipses expected to be visible from Spain between now and 2028.
In a statement issued by the agency, ESA director of science Carole Mundell said that a total solar eclipse represents a rare moment when millions of people can look at the sky together in awe and curiosity. She described it as a shared moment connecting humanity to the universe and serving as a reminder that the desire to explore and understand is one of humanity's greatest strengths.
Path of Totality Across the Northern Hemisphere
According to astronomical tracking group EarthSky, the narrow path of totality will stretch 8,300 kilometers (5,157 miles). It will originate over the Arctic coast at approximately 1:00 p.m. Brasilia time (13:00) and pass near the North Pole before tracking across Greenland, Iceland, Portugal, and northern Spain.
The duration of totality will vary significantly depending on observation location. Skywatchers situated in Greenland will be able to observe the total eclipse for slightly more than two minutes. Conversely, observers in northern Spain will experience totality for only about 20 seconds, provided atmospheric conditions permit. Weather conditions remain the single largest obstacle to successful eclipse viewing.
The Spanish Scientific and Advisory Committee for the Eclipse Trio noted that the eclipse path will move through Galicia and terminate over the Balearic Islands in eastern Spain at nightfall, accelerating the shift from day to night.
For observers located outside the path of totality, the European Space Agency plans to broadcast a live online stream of totality directly from the Javalambre Astrophysics Observatory located in Teruel, Spain. Skywatchers can also consult the Time and Date website to check precise local schedules and visibility levels for their specific region.
Future Total Solar Eclipses Around the World
Following the August event, NASA projects that the next total solar eclipse will occur on August 2, 2027. That path of totality will pass over southern Spain, northern Africa, Saudi Arabia, and Yemen.
Opportunities to view total solar eclipses from the United States will remain rare over the coming decades. The United States will not see another total solar eclipse until March 30, 2033, when totality will be visible exclusively from Alaska.
Viewers in the contiguous United States will have to wait until August 22, 2044, to witness totality, which will be visible only across North Dakota and Montana.
A broader cross-country total solar eclipse will sweep across the 48 contiguous states on August 12, 2045. That path of totality will traverse California, Nevada, Utah, Colorado, Kansas, Oklahoma, Arkansas, Mississippi, Alabama, and Florida, while other states will observe a partial eclipse.
Eye Safety Guidelines and Equipment Standards
Experts warn that looking directly at the sun without specialized eye protection is extremely dangerous at any time, except during the exact period of totality when the sun is completely covered by the moon.
Viewers must put on certified eclipse glasses or use a handheld solar viewer at the first sign of reappearing sunlight. Alternatively, observers can view the event using a camera, binoculars, or telescope fitted with a specialized solar filter over the lens, which provides the same eye protection as eclipse glasses.
Standard sunglasses cannot be used as a replacement for certified eclipse glasses or handheld viewers. Purpose-built solar filters are thousands of times darker than regular sunglasses and strictly comply with international safety standards. Damaged, scratched, or torn solar filters should be discarded immediately.
NASA explicitly warns against looking at the sun through any optical device, such as camera lenses, telescopes, or binoculars, while wearing eclipse glasses or using a handheld solar viewer. Optical lenses concentrate solar rays, which can rapidly burn through the protective filter of eclipse glasses and cause severe, permanent eye damage.
Scientific Research and Relativity Experiments
Beyond providing a skywatching spectacle, total solar eclipses afford scientists valuable opportunities to analyze the sun and its outer atmosphere, known as the solar corona, while inviting the public to participate as citizen scientists.
During the August event, researchers intend to launch high-altitude balloons equipped to capture images of the event and the lunar shadow.
According to the Spanish Scientific and Advisory Committee for the Eclipse Trio, the balloon project aims to replicate a landmark 1919 eclipse experiment. That historical test measured how the gravitational field of the sun bends light emitted by distant stars, providing early empirical proof for Albert Einstein's theory of general relativity.
Scientists are also calling on members of the public to participate as citizen scientists by constructing their own instruments to measure atmospheric changes as the sky momentarily darkens.
Mundell noted that space organizations leverage such moments to bring space science and technology closer to society, inspire future generations, and unite people across Europe through the excitement of discovery.
