Category: Eclipses

On Aug. 21, 1914, a total solar eclipse temporarily darkened skies across Europe and Asia. A young German astronomer and friend of Albert Einstein's, Erwin Finlay-Freundlich, led an expedition to the Crimean Peninsula of Russia, where he hoped to record observations that would verify Albert Einstein's general relativity theory.

This theory predicted that the light from distant stars appearing very close to the sun's edge should shift due to the curvature of space. Those stars would only be visible during a total solar eclipse, when the moon blocks out the sun's bright light. Unfortunately, the start of World War I just 20 days before the eclipse foiled the expedition. After Germany declared war on Russia, Freundlich and his colleagues were captured by the Russian army and their equipment was confiscated.

After the war, a solar eclipse on May 29, 1919 was used to confirm Einstein's theory of general relativity, so the experiment was ultimately a success.

Why it mattered

Today, Einstein's general relativity theory is a given. This theory is firmly cemented in our modern understanding of how the universe works (not counting fringe conspiracists). But looking back just over 100 years, it is interesting to see how hard scientists had to work to gather evidence to validate this theory and consider the way war and geopolitics played a part in postponing this work.

Scientists continue to validate the theory to this day through a variety of methods and observations, though a modern trek to witness a total solar eclipse would be a lot easier than it would have been in 1914.

This expedition, or rather the planned expedition, took place well over 100 years ago. Whether for the purposes of trying to validate Einstein's general theory of relativity or just for fun, people have experienced eclipses for as long as we can date back.

It's fascinating to look at the parallels between this planned expedition over 100 years ago and the treks that people around the world (including Space.com reporters) take in modern times to see a total solar eclipse. For example, during the 2026 total solar eclipse, people flocked from all over to locations like Spain and Iceland to experience the eclipse far from home.

When the 11,000-ton cruise ship Le Boréal set sail from Nice, France, on Thursday, Aug. 6, its 205 passengers and 136 crew members began a voyage whose success would depend not only on careful planning, but also on the ship's ability to outmaneuver clouds at the last critical hour.

The ship is owned and operated by the French cruise line Compagnie du Ponant. This eclipse cruise was the result of more than a year's planning by Ponant, and most of those who signed on were there specifically to witness the celestial spectacle; that shared purpose heightened the drama of the eclipse itself.

This was going to be a sunset eclipse, with the sun no more than three degrees above the horizon. To picture that height, make a fist and hold it out at arm's length. Place the bottom of your fist on the horizon; the top of your fist measures about ten degrees. During totality, the sun would appear only about one-third of a fist-width above the horizon. Even if the sky overhead was clear, clouds could still gather near the horizon, leaving open the possibility that the sun might be hidden at the critical moment.

I was on board Le Boréal as both a lecturer and the ship's onboard meteorologist. The main advantage of using a cruise ship to view an eclipse is its two-dimensional mobility, allowing it to maneuver around potential cloud cover. In practice, that meant working with Captain Mathieu Tsingrilaras to position Le Boréal on eclipse day in a location free of any clouds that might otherwise obscure the total eclipse.

Although the Iberian Peninsula and the adjacent waters of the Balearic Sea — a body of water between mainland Spain's eastern coast and the Balearic Islands — typically enjoy warm, dry, clear weather in August, the circumstances of this eclipse could still prove problematic.

Also serving as a lecturer for the cruise was Serge Brunier, a well-known French photographer, reporter, and writer who has specialized in popular depictions of astronomical subjects. He is also the co-author of the beautiful coffee-table book, Glorious Eclipses.

Serge would accommodate the French-speaking passengers onboard. Early in the cruise, as we were speaking with each other, a French passenger came up to Serge and asked, "Le temps sera-t-il dégagé pour l'éclipse?" ("Will we have clear weather for the eclipse?"). Serge nodded toward me and replied: "Il faudra demander à Joe ; c'est lui qui s'occupe de la météo." ("You will have to ask Joe; he is in charge of the weather.")

Our itinerary took us to many different places during our eight-day cruise, including two towns in Corsica (Calvi and Bonifacio), the French cities of Marseille and Port-Vendres as well as Spain where we stopped at Barcelona and Palma de Mallorca in the Balearic Islands. Through it all, we experienced weather that was mainly sunny, very warm and quite humid. An upper-level ridge of high pressure acted as a heat dome over much of Europe.

Weather threat on eclipse day

The first warning came on Aug. 10, when a minor disturbance rippled through the heat ridge and produced widespread clouds, showery rains and thunderstorms across eastern Spain, spilling into the eclipse zone over the adjacent Balearic Sea. Had the eclipse taken place that day, no amount of mobility would have brought us a clear view. Fortunately, the disturbance quickly moved east, allowing high pressure to build back over the region.

By eclipse day, Aug. 12, conditions appeared to have turned in our favor. The day began beautifully sunny and continued that way into the afternoon. Our ship was docked at Palma de Mallorca, then set sail at 4 p.m. Central European Summer Time (CEST) for our preselected viewing location, heading west-northwest along the center line of the path of totality.

Shortly after departure, images from EUMETSAT, a geostationary weather satellite looking down from 22,000 miles (35,400 km) above Europe, revealed the problem we had been trying to avoid.

A large convective cloud — formed when warm, damp air rises into colder air above — began to rapidly evolve over part of Spain's coastline just inland from the Gulf of Valencia. It soon became apparent that if we did not alter course, that cloud would almost certainly block our view of the total eclipse.

After consulting with Captain Tsingrilaras, we decided to take Le Boréal southwest. That maneuver would cause the cloud, then directly ahead of us, to shift to the right of the sun as it descended the west-northwest sky, improving our odds for viewing totality.

That course correction became the turning point of the voyage.

Totality at sea

As the eclipse began, other cruise ships apparently stayed their original courses. Le Boréal's course change, however, kept us clear of significant cloudiness, aside from a few thin clouds that occasionally crossed the sun but did little to hinder the show. At 7:37 p.m. CEST, the moon took its first bite out of the lower right limb of the sun.

At 8 p.m., Captain Tsingrilaras oriented Le Boréal, so that the back of the ship (the stern) faced directly toward the sun. Crowds gathered on the top three decks of the ship, observing the sun through special eclipse glasses that had been distributed the previous evening.

Moments before totality, when only a sliver of sun remained, I told passengers that I had been asked since the start of the day about what our chances were for seeing the total eclipse. "I think our chances of seeing it are now 100 percent!" That comment was met with a resounding cheer.

What was particularly striking was the approach of the moon's shadow; a diffuse darkening accompanied by a rapid west-to-east sweep of darkness. The onset of totality was marked by a dazzling diamond ring effect which lasted a couple of seconds, then a circular corona appeared around the darkened solar disk; it appeared somewhat yellowish in color as opposed to pearly white, likely due to a layer of haze near the horizon.

An unusually large and brilliant red prominence, readily visible even with the unaided eye, appeared at the 9 o'clock position. Because the sun was so low in the sky, the famous moon illusion caused it to appear especially large. This only added to the beauty of the spectacle.

Totality lasted 95 seconds. Even at its midpoint the overall light never became so dim that the second hand on a watch was hard to see. The only other object that was plainly visible in the sky was Venus, well off to the upper left of the eclipsed sun. The air temperature did not change much, probably due to the thermal inertia of the surrounding water.

The terminal diamond ring was perhaps even more stunning than the first. The corona could be kept in view for several seconds by blocking out the emerging crescent of sunlight with one's thumb. It seems that no shadow bands were observed either before or after totality.

As the sun gradually emerged from behind the moon, it sank lower in the sky and was still about two-thirds covered when it took on the shape of an orange-red shark fin disappearing beyond the horizon — a fitting final image for a spectacular eclipse at sea.

Nothing succeeds like success

In the end, Le Boréal's successful eclipse viewing was a reminder that even the most carefully planned astronomical event still depends on swift judgment and adaptability. By combining advance preparation with a timely course correction, the voyage transformed a looming weather threat into an unforgettable view of totality.

I would also like to thank my wife, Renate, who accompanied me on this amazing adventure and for reading so much for reading my first draft of this article and to my daughter Maria and Scott Zimmerman for assisting me with my video and image selections.

Joe Rao serves as an instructor and guest lecturer at New York's Hayden Planetarium. He writes about astronomy for Natural History magazine, Sky and Telescope, The Old Farmer's Almanac and other publications.

I woke up on the morning of Aug. 12 and looked out of the window to something I hadn't dared hope for: blue sky.

After days of scrutinizing weather models that seemed determined to test the nerves of everyone aboard the HX Expeditions ship MS Spitsbergen, somehow, against the odds, the clouds had cleared. Even then, I didn't trust it (especially after my 2024 eclipse experience). We had traveled thousands of miles, crossed the Greenland Sea and ventured deep into Scoresby Sund to put ourselves in the path of the moon's shadow. Now there was nothing to do but wait — and hope the sky stayed clear.

The wind howled across the deck, but nobody seemed to mind. If anything, it was helping us, keeping the clouds at bay. The atmosphere aboard felt like Christmas Eve with a ship full of overexcited children. Some guests had chased eclipses across the world; for others, this would be their first. Either way, Aug. 12 was the date we'd been waiting years for.

But by the time we reached Scoresby Sund, something had shifted.

I had traveled all this way to look up. Instead, I found myself looking around. I'd come here for 2 minutes and 14 seconds of darkness. Instead, Greenland had spent the previous days relentlessly demanding my full attention.

After a couple of days at sea during the crossing from Svalbard to East Greenland, our first sight of land appeared almost like a mirage on the horizon. Soon, icebergs were drifting past the ship and the scale of the landscape became increasingly difficult to comprehend. We could sail for hours through Northeast Greenland National Park without seeing a single sign of human civilization beyond our own ship. At times, moving through those immense geological landscapes felt less like traveling across Earth and more like exploring some distant, icy-covered moon.

Yet, the more otherworldly Greenland appeared, the more it made me appreciate our own planet.

At times it felt as though I'd stepped into a geology textbook. Processes and structures I'd previously seen reduced to diagrams were suddenly towering above me. And amongst all the enormity were the tiniest signs of life: lichens and miniature Arctic plants hugging the ground beneath vast mountains and glaciers.

The scale and contrast were overwhelming at times, and no view stayed the same for long.

An iceberg viewed from one side could morph into a completely different form as the ship sailed past it. A break in the clouds could transform a gray mountainside in seconds. In Scoresby Sund, even the ice seemed to echo the landscape around it as jagged peaks, flat-topped slabs and sculpted ridges rose from the water like miniature versions of the colossal mountains behind them.

The Greenland scenery was a gift that kept on giving, and I found myself increasingly reluctant to go inside. I began meticulously scanning for wildlife, because I'd learned how quickly something extraordinary could appear.

On an impromptu evening walk in Longyearbyen before we set sail, beluga whales had suddenly surfaced in the bay. Later, in Greenland, while I was distracted by a spectacular circumzenithal arc and sundogs overhead, one of a handful of people still standing on deck spotted two tiny white shapes in the water. I thought they were birds bobbing along.

Then I lifted my camera and zoomed in.

Polar bears.

It became something of a lesson for the expedition: stay curious, keep your eyes open and remember to look both up and down.

That curiosity seemed to unite everyone aboard. Guests had traveled from around the world for this eclipse opportunity. There were seasoned eclipse chasers looking to experience totality somewhere extraordinary, first-timers who had no idea how they would react and people drawn as much by the adventure and wildlife, as the eclipse itself.

HX Expeditions' onboard science and education programme gave that shared enthusiasm somewhere to go. Our days were filled with nature landings, lectures, citizen-science projects and conversations with experts, helping us do more than simply travel through Greenland. The programme encouraged us to pay closer attention — not merely to see the landscape, but to understand and truly experience it.

Conversations jumped from eclipses to wildlife, travel, geology and perhaps, inevitably for a ship full of skywatchers, clouds. We took part in the GLOBE Observer cloud citizen science project and found ourselves happily studying them — while collectively hoping they would be nowhere near the sun on eclipse day.

The eclipse had brought us together, but the journey had quickly become about much more.

Then, on Aug. 12, our attention returned to the sky.

When the moon took its first tiny bite from the solar disk, excitement rippled across the deck. For the next hour, it steadily consumed more of the sun.

As totality approached, the quality of the light began to change.

It became strangely yellow and dull, yet at the same time the landscape seemed almost unnaturally sharp. It was eerie — familiar enough to still resemble daylight, but wrong enough that your brain knew something extraordinary was happening.

What amazed me most was how long that daylight persisted.

Even when only the tiniest sliver of sun remained, Greenland was still illuminated. I knew scientifically how intensely bright the solar photosphere is, but knowing it and watching that minuscule fraction of sunlight continue to illuminate an entire landscape were two very different things.

Then the final fraction disappeared.

The world around me plunged into twilight.

And there it was.

Totality.

I knew exactly what I was supposed to see. I've written about eclipses for years. I understand the science. I had seen thousands of photographs of the corona, prominences, Baily's beads and diamond rings.

None of it prepared me for the feeling of actually seeing one.

The first thing that struck me was how large the eclipsed sun appeared to the naked eye. Photographs had never prepared me for that sense of scale, nor how much detail I could see with my own eyes.

The moon itself looked impossibly dark — a black void punched into the sky — surrounded by the pearly white corona. Long streamers stretched away from the sun and around the moon's edge I could see bright pink prominences.

I was so surprised to see this vivid pink color with my own eyes. For 2 minutes and 14 seconds, I saw the sun as I had never seen it before.

But even then, I couldn't just look up.

I looked around. Jupiter and Mercury shone clearly off to one side of the eclipsed sun, with Mercury far brighter and easier to spot than I had expected. Venus blazed on the other side.

Then I looked down. Below the eclipsed sun were icebergs. Beside us rose the immense walls of Scoresby Sund. Glaciers carved their path through the landscape.

Above it all hung that black disk and its enormous, delicate corona. My brain simply couldn't take it all in.

There was too much beauty. Too much scale. Too much happening at once.

People use words such as "mind-blowing" and "speechless" so often that they begin to lose their meaning.

But my mind was really blown. And I really was speechless. Perhaps the best way I can describe it is that my mind felt full, but quiet. Full because there was almost too much to comprehend, but quiet because for those fleeting moments, there was room for nothing else.

The intensity of the experience surprised guests who had originally joined the voyage for different reasons.

"My husband and I came to see the wildlife, and we were actually in awe of what we saw in relation to the solar eclipse," Kenya Haupt, from Colorado, told Space.com. "Truly an emotional experience"

The reasons for joining the expedition varied, but beneath the moon’s shadow, the experience became a collective one.

For Shubhada Maitra, from India, it was her first total solar eclipse.

"When I looked around me, I just had a feeling that we were one community, taking part in one of the most spectacular, perhaps once-in-a-lifetime celestial events," Maitra said. "Although we came from different countries, different nationalities, genders, all of that, that solar eclipse just bound us together."

"Without saying anything, we were just so connected in that experience."

Lisa Marie Morse, from Rhode Island, described the eclipse as both "joyous and melancholy."

"In that moment of darkness, I felt a powerful connection with all living things, to an infinite ancient rhythm locking us together for 134 seconds of shared awareness, then releasing us back into our daily slumber," Morse said. "It was magical."

Then, almost as quickly as totality had arrived, it was ending.

The first brilliant beads of sunlight appeared from behind the moon.

They were beautiful, but there was a sadness in seeing them too. The corona, prominences and extraordinary black void that had dominated the sky were about to disappear once more into the overwhelming glare of the sun.

Two minutes and 14 seconds had somehow felt both packed with experience and impossibly brief. I had just enough time to look with my naked eye, search for planets, check it out through binoculars and try to absorb the reactions around me.

Then it was gone.

For seasoned eclipse chaser Roy Tillcock from the Isle of Wight, the clear view had come as a genuine surprise.

"This was one of the most unexpected eclipses I've seen," he said. "I did not have high hopes of seeing it, and there it was. Brilliant."

And, as if to underline just how fortunate we had been, the clouds rolled in shortly after totality. A few minutes later, and this could have been a very different story.

Some skywatchers were emotional. Others were exhilarated. Many, like me, seemed to be struggling to find words big enough for what had happened.

Perhaps that is part of why eclipse chasing becomes so addictive. We can explain the science of totality in extraordinary detail. We can calculate the path of the moon's shadow years in advance, travel thousands of miles to stand beneath it and know exactly when and where darkness will fall.

But knowing what to expect is not the same as experiencing it.

The following morning, Greenland was still there, still demanding my undivided attention. Icebergs drifted past the ship. Mountains towered above the fjord. The sunlight shifted and the landscape transformed once again. I had traveled all this way to look up.

But somewhere along the journey, I had learned to truly look around. Here I was, standing on a planet of glaciers, oceans, wildlife and ancient rock, watching its moon pass perfectly across its star at a moment in Earth's history when their apparent size in our sky happened to match. How lucky are we to experience any of this? Luck, ultimately, is something no eclipse chaser can ignore.

We could calculate where the shadow would fall. We could sail into its path. We could scrutinize forecasts, prepare our equipment and position ourselves as carefully as possible.

But we couldn't command the clouds to cooperate.

Nature always has the final say. And on Aug. 12, 2026, in a remote fjord in East Greenland, nature said yes.

Editor's note: This trip was made possible by travel and accommodation provided by HX Expeditions.

This week's total solar eclipse captured the world's attention, and millions of skywatchers looked up (with the correct protective eyewear, hopefully) to experience the moon blocking out our star's light. And, as you can see in this image, even the International Space Station (ISS) itself got in on the fun.

What is it?

On Aug. 12, 2026, the moon completely blocked out the sun's light for millions of lucky skywatchers witnessing a total solar eclipse.

But the moon isn't the only thing orbiting Earth. Tons of satellites and probes do too, and that includes the ISS. This created a truly remarkable moment for some skywatchers. With the right equipment, it was possible to see the silhouette of the ISS in front of the sun.

This composite image shows eight different frames of the ISS silhouetted on the sun's face as the moon takes a "bite" out of our star to create a partial eclipse.

Why is it incredible?

Solar eclipses like this week's total solar eclipse really bring people together. It creates opportunities for humans to come together and gather for a common goal.

And while the ISS is featured in this image, we may also want to consider the astronauts aboard. In other words, people on Earth weren't the only ones who got to participate in the marvel.

The Expedition 75 astronauts on the ISS (NASA astronauts Jessica Meir, Anil Menon, and Jack Hathaway; ESA (European Space Agency) astronaut Sophie Adenot; and Roscosmos cosmonauts Pyotr Dubrov, Andrey Fedyaev and Anna Kikina) caught the show too as they orbited our planet. There they were, in between Earth and the moon, as our planet's neighbor blocked out our star.

The total solar eclipse of Aug. 12, 2026 was one for the books. And this photo, snapped just as the eclipse was about to enter totality, really captures the drama of the moment.

What is it?

On Aug. 12, 2026, millions of people around the world witnessed a total solar eclipse. This happens when the moon passes in front of the sun, completely blocking it from our perspective here on Earth. (During a partial solar eclipse, only part of the sun's face is blocked by the moon.)

Observers lucky enough to be in the narrow "path of totality" that day got an experience they'll never forget.

Why is it incredible?

The chance to observe a total solar eclipse doesn't come along very often and is truly surreal and magical. While you might logically know that it's a predictable result of orbital dynamics, it's still incredibly strange in the moment to watch the sun disappear behind a black disk.

During totality, you experience a sort of false nighttime in the middle of the day. This can trigger strange responses from wildlife, with animals that are typically nocturnal coming out to see what's going on, confused about why night arrived at what feels like the wrong time.

Space.com skywatching editor Daisy Dobrijevic traveled to the Scoresby Sund off the coast of Greenland to experience the total solar eclipse from the deck of the MS Spitsbergen on the HX Expeditions eclipse voyage, and she's been taking us all along on her journey.

"I couldn't believe my eyes. I knew exactly what to expect — I’ve written about total solar eclipses countless times and given talks about them — but nothing prepared me for the feeling of actually seeing it," Dobrijevic said about her experience watching the eclipse. "I was completely in awe. As thin clouds drifted in towards the end of totality, they only added to the drama and emotion of an already extraordinary sight."