Time-lapse video taken from Croatia at around 4 p.m. EST, or 9 p.m. local time, shows the glowing light spinning across the sky in what many social media commentators likened to a spiral galaxy.

The simple answer is no. Instead the blue light we see is scattered sunlight. The Sun produces a broad spectrum of visible light, which we see as white but it includes all the colors of the rainbow.

A weird blue spiral of light, captured on photo in the night sky? As much as we might want it to be, we know by now that it's not aliens (it's never aliens, OK?). But little green men aside, the ...

The simple answer is no. Instead the blue light we see is scattered sunlight. The sun produces a broad spectrum of visible light, which we see as white but it includes all the colors of the rainbow.