Milky Way, Aurora, and Airglow

The World Heritage Site of Banff National Park in Alberta, Canada, is a favorite destination of TWAN photographer Yuichi Takasaka to enjoy the dark starry sky, another natural heritage which is still preserved here. The wide-angle image not only captured the Milky Way, also green and red aurora at the northeast horizon. To the upper left of the aurora several faint bands are visible in the sky. This is air-glow, an atmospheric phenomenon which is the natural night-time radiation of the upper atmosphere, very often appears as faint bands in the visible lights and brighter in the infrared.