NASA photographer John Grant has captured a strange sight above the Marshall Islands in the Pacific.
The odd blue clouds look like a unique aurora hanging in the sky - and at first glance it's easy to think it could be evidence of a UFO, or some other strange phenomenon.
Fortunately for our sense of reality, it's neither of those things.
In fact the picture was taken shortly after the launch of two sounding rockets launched from Roi Namur on 7 May.
The rockets are part of an attempt to study how winds and electrical activity works in the upper atmosphere.
The white-blue cloud was made by the release of trimethyl aluminium, while the red cloud above it was made by lithium vapour.
These chemicals were released intentionally to help study how the winds in the ionosphere - known as neutral winds - work.
Universe Today has more details on the experiment - but some of the other best clouds captured by Nasa's cameras are copied below.