(CNN) -- Winter travelers trek thousands of miles to the frozen north each year seeking the sky's "dancing lights," which provoke awe, excitement and, some say, sex.



CNN iReporter Bruce Barrett shot this rare red aurora in Canada's Whitehorse, Yukon.



Scientists call the natural phenomenon aurora borealis: cascading beams of greens, yellows, blues, purples or reds -- which paint a breathtaking backdrop across the wilderness and attract thousands of tourists annually.



"Usually it starts slowly as kind of a hazy greenish color -- like a mist -- building up in frequency dancing across the sky ... and to me that's religion," said photographer Dave Brosha of Yellowknife, Northwest Territories, who's seen more than 100 Canadian auroras. "It's just one of the most incredible feelings a person can have -- sitting there watching that."



To the west in Canada's Yukon province, tour operator Torsten Eder likes to tell a story about a marriage that was forged under the glowing curtains of light.  See spectacular photos of auroras »



"I had one guy from Mexico, and he wanted to surprise his girlfriend by proposing marriage with a ring under the northern lights," said Eder from his office in Whitehorse.



"We got lucky and the lights were visible ... so our guest went down on his knee and proposed to his girlfriend and she was totally blown away. The funny thing was -- she wouldn't wear gloves for the first three days -- so she could show the ring off."



The otherworldly lights also have provided inspiration for almost sacred pilgrimages, Eder said. Guests who said they were going blind or battling cancer told him they wanted to view the auroras at least once in their lives.



"It puts enormous pressure on us," said Eder. "You can't guarantee that the lights will be visible because it's a natural phenomenon." The display is generally visible at least every three days, he said.



Scientists say the northern lights are created by the sun's super hot atmosphere, which blasts particles into the protective magnetic field surrounding the Earth. The magnetic field forces the particles toward the north and south poles. About 60 to 200 miles overhead, the particles bump into the Earth's atmosphere and become electrically "excited" -- throwing off light of various colors, said Prof. Dirk Lummerzheim of the University of Alaska, Fairbanks.



"The forecast for this winter is a continued quiet sun, in general," he said. The sun is on the upswing of an 11-year cycle. "Maybe we will have a few periods once a month where the aurora can get a little bit more active."



Although the phenomenon occurs around the clock, the lights are only visible at night. The best time of year to see them is during winter, when darkness in the upper latitudes stretches up to 24 hours.  See map where northern lights can be seen »



Eder's Northern Tales tour company picks up guests at their hotels about 10 p.m. and takes them to an area about 20 minutes outside Whitehorse's city lights. There, travelers can enjoy nature's colorful show from a heated, walled tent until around 2 a.m.



"We almost take it for granted sometimes," said Brosha. "No matter how many times you've seen the aurora borealis -- when they really dance, when you get some really unique colors -- you just kind of say, 'Wow, I'm so lucky to see that.' "



A warmer way to enjoy the northern lights is a shallow, natural rock lake at Chena Hot Springs outside Fairbanks, Alaska, which allows bikini-clad guests to enjoy the lights in temperatures of 106 degrees Fahrenheit.



"I mean, honestly, it's the best way to see them," said spokeswoman Denise Ferree. "Because you're warm and toasty and you're watching the northern lights above."



Chena's owner, Bernie Karl -- who's often as colorful as the lights themselves -- said the auroras sometimes spark the libido.



"Having sex under the northern lights -- it's an
Who seeks the aurora borealis? who saw this phenomenon which it is the name of this person What is an awesome experience? What colors are the dancing lights?
Winter CNN iReporter Bruce Barrett Bruce Barrett "Having sex under the northern lights cascading beams of greens, yellows, blues, purples or reds
question: Who seeks the aurora borealis?, answer: Winter | question: who saw this phenomenon, answer: CNN iReporter Bruce Barrett | question: which it is the name of this person, answer: Bruce Barrett | question: What is an awesome experience?, answer: "Having sex under the northern lights | question: What colors are the dancing lights?, answer: cascading beams of greens, yellows, blues, purples or reds