The Northern Lights, or aurora borealis , are believed to be the result of solar winds entering the Earth’s ionosphere some 160 km (100 miles) above the surface of the planet. Emanating from the sun, these winds collide with the gases present in the Earth’s upper atmosphere, releasing energy that becomes visible in the night sky. The stunning consequences are visible in the Yukon and the NWT, most often from August to October. Some aboriginal groups attach religious significance to the Lights, believing them to be the spirits of dead hunters, while 19th-century gold prospectors mistook them for vapors given off by ore deposits. Whatever one’s beliefs, the sparkling ribbons of light are an awesome sight.