(Source: Timpaanen, Wikicommons).
In 1880, Prince George of Wales, the future king of England, then in his teens, saw it during a sea voyage. As he wrote in his journal, “July 11th. At 4 a.m., the Flying Dutchman [the legendary ghost ship] crossed our bows. A strange red light as of a phantom ship all aglow… stood out in strong relief… thirteen people saw her.” News of the sighting spread like wildfire on the ship. To superstitious sailors, sighting such a phantom ship sailing in the air above the ocean was a dire omen. Or was everyone just imagining it?
During a recent visit to a friend who lives right on the Salish Sea near Seattle, he told me to watch for a Fata Morgana over the water. A what? He explained that a Fata Morgana is a type of mirage common in this area. Sure enough, the next day we saw one. The buildings on the far shore opposite his deck appeared larger, seeming to hover in the air.
Mirages happen when atmospheric conditions team up with assumptions our brains make. On some days, the cool waters of the Salish create a layer of colder air just above the surface. If a layer of warmer air forms above the colder air, conditions are right for a Fata Morgana. When sunlight travels from the warmer upper air into the cooler lower layer, the sunlight bends slightly. We think of light as always traveling in straight lines, but this is not always true. If the light moves from a less dense medium, say warmer air, into a denser medium such as cooler air, the light rays will bend. Physicists call this bending “refraction”, and we can easily see this by putting a pencil in a glass of water. The pencil looks bent, but of course, it is not.
When our brain receives the refracted light, it assumes that the light traveled in a straight line, so our brain creates a vision of a ship or buildings in the distance, hovering above the horizon. This is yet another case of us not seeing what is actually there, but we see the image our brain assembles. If you want to touch the tip of the pencil in the water glass, reach above the image you see in the glass. People spearfishing learn to adjust to where the fish is, not where their eyes tell them it is. Scientists believe that the eyes of birds who fish in shallow water make this adjustment automatically.
Fata Morgana get their name from the sorcerer of legend, Morgan le Fay, the fairy half-sister of King Arthur. Fata Morgana is the Italian version of the name since this type of mirage is very common in the Straits of Messina. These visions terrified early sailors and some historians think that these Fata Morgana mirages were behind the stories of the Flying Dutchman, an eerie ghost ship reputed to float in the air. Some scholars believe that a Fata Morgana might have played a role in the tragedy of the Titanic. They say one of these mirages may have obscured the fatal iceberg when there was still time to turn the gigantic ocean liner.
Fata Morgana can appear whenever conditions are right, on shore or at sea, on the water or in the desert. Sometimes the images are right side up or they may be upside down. They may make the images look bigger or just closer. The images we saw were bigger and suspended in the air. It was quite a contrast to look the next day and see the far coastline back to “normal.” Sometimes, a mirage will show an image below the horizon. Some places like the Straits of Messina and the Great Lakes region frequently have just the right conditions for these mirages.
In one version of Prince George’s story, when the captain of the vessel heard the tale, he came to the deck and explained to the crew that the apparition was simply a mirage. This could happen, he told them when the atmospheric conditions were just right. He sent a sailor up to the foretop for a better look. The sailor reported he could now see a ship in the water exactly like the one that had appeared to float in the air. This calmed and convinced the terrified sailors.
We need more trusted Explainers, like this captain, for all the superstitions rampant in our world today.
Sources:
STEM & Creative Change 