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.

In the spring and summer, you’re more likely going to see a light blue sky. Sometimes, it’s kind of a milky appearance, and some days, it can be so light it almost looks white.

In the spring and summer, you’re more likely going to see a light blue sky. Sometimes, it’s kind of a milky appearance, and some days, it can be so light it almost looks white.

When millions of people turn off their lights for Earth Hour each year, something remarkable happens in the night sky above ...

In the spring and summer, you’re more likely going to see a light blue sky. Sometimes, it’s kind of a milky appearance, and some days, it can be so light it almost looks white.

Sometimes, it’s kind of a milky appearance, and some days, it can be so light it almost looks white. But in the fall and winter, you’re more likely to see richer shades of blue.