A Fata Morgana is actually an unusual and complex superior mirage occurring in a narrow band on the horizon. The term Fata Morgana is often applied to more common types of mirages, but a true Fata Morgana is not the same. One can be seen on land, at sea, in Polar regions or in deserts. It can involve any kind of distant objects such as boats, islands and coast lines. Objects are distorted, inverted and right side up, stacked on top of each other and may change rapidly.
This optical illusion occurs when light rays and radio signals bend passing through layers of different temperatures creating an atmospheric duct that acts as a lens producing inverted and erect images. A true Fata Morgana requires a duct to be present . A thermal inversion is not enough to produce this kind of mirage.
An observer needs to be within or below an atmospheric duct to be able to see a Fata Morgana. They can be seen from any altitude, from sea level to mountain tops, even from airplanes. Because of constantly changing conditions, it can be seen in various ways in only a few seconds then rapidly changed into a simple mirage. They can be seen by the naked eye, but to see detail within them, its best to view them through binoculars or telescope or telephoto lens.
There are many recorded observances and many myths are attributed to them. One of the most famous legends is The Flying Dutchman, the phantom ghost ship that is doomed to sail the oceans forever. Seen at a great distance, it is sometimes seen glowing with a ghostly light . The mirage is a refraction due to the layers of air when a real ship is out of sight because its below the horizon line. If the ship is above the horizon, the image can be duplicated and elaborately distorted.
A remarkable mirage, but not a Fata Morgana, was witnessed by approximately 20,000 spectators at Buffalo, N Y the morning of August 16, 1894. This mirage was the kind where objects loom high into the sky and are not distorted. This looming mirage was a perfect landscape of the city of Toronto, 56 miles from Buffalo, complete with its harbor and small island with its church spires clearly defined. It took in the whole breadth of Lake Ontario. It remained visible until a cloud bank obscured the mirage.
Many observers are still tricked by this phenomenon. Today, no one believes in The Flying Dutchman, but many are mistaken for UFOs. Some UFOs are seen on radar. Conditions for radar mirages are common due to the role of water vapor, which affects atmospheric refraction in relation to radio waves.
Serious Arctic expeditions ensued after misinterpreting displays of a Fata Morgana. Sir John Ross' expeditionary voyage, searching for the long sought after Northwest Passage, saw a land mass he believed would prevent further exploration. He named it Croker Mountain, after the First Secretary to the Admiralty, John Croker. Robt Peary's 1906 Arctic expedition named a land mass Crocker Land honoring a San Francisco banker, one of the financial backers of the expedition.
Beset by trials, tribulations and murder, an Arctic expedition to map and investigate Crocker Land was organized by Donald Baxter Macmillan in 1913 and sponsored by the American Museum of Natural History, American Geographical Society and the University of Illinois' Museum of Natural History.
On 11th of April, four members of the expedition, McMillan, Navy Ensign Fitzhugh Green, and two Inuit, Piugaattoq, Ittukusuk, set off in the direction of Crocker Land, crossing treacherous sea-ice, avoiding thin ice patches and expanses of open water. On 21st of April they saw what appeared to be a huge island on the horizon. They could see hills, valleys, and snow capped peaks. Piugaattoq, an Inuit hunter with 20 years experience in the area explained that it was just an illusion, calling it “poo-jok” meaning mist.
Ignoring the Inuit, McMillan insisted on pressing on despite the lateness of the season and the sea-ice breaking up. After traveling a further 125 miles, McMillan was forced to admit Piugaattoq was right. Turning back, the group was lucky to regain solid land before the sea-ice broke the next day.
Having reached safety, McMillan sent Green and Piugaattoq to explore a route to the west but worsening weather forced them to shelter in a snow cave. One of the dog teams died in the snow. In a squabble over the remaining team, Green took a rifle from the sled and shot Piugaattoq, killing him.
Rejoining McMillan, Green told what happened. McMillan later informed the European members of the expedition and asked them to keep it quiet. They told the Inuit that Piugaattoq had died in the blizzard. The geologist- ornithologist- botanist, Walter Elmer Ekblaw remarked “...one of the darkest and most deplorable tragedies in the annals of Arctic exploration”. Green was never prosecuted for murder. The Inuit suspected there was more to the story than had been told. Green had a relationship with Aleqasina, wife of Piugaattoq and a striking beauty. She had previously been Peary's mistress and had born him two children.
The expedition ended up stranded in the region for 4 years due to weather. Several ships attempted rescue but they were in turn stranded and forced to turn around. Green and two other members made their way back to the United States by dog sled. The rest of the expedition was rescued in 1917.
Fata Morgana
Henry Wadsworth Longfellow 1873.
O Sweet illusions of song
That tempt me everywhere
In the lonely fields, and the throng
of the crowded thoroughfare!
I approach and yet ye vanish away
I grasp you, and ye are gone
But ever by night and by day
The melody soundeth on.
As the weary traveler sees
In desert or prairie vast
Blue lakes, over hung with trees
That a pleasant shadow cast.
Fair towns with turrets high
And shining roofs of gold
That vanish, as he draws nigh
Like mists together rolled
So I wander and wander along
And before me ever gleams
The shining city of song
In the beautiful land of dreams
But when I would enter the gate
Of that golden atmosphere
It is gone and I wonder and wait
For the vision to reappear.
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