Can you spot what's weird with this picture?

This beautiful picture taken by photographer Kevin Wolf in California's Yosemite National Park. has us all baffled and in a thick debate - Was this picture taken during the day or at night?

The top of the image is a star-filled dark blue night above a huge mountain and the trees look like they're shedding their leaves in Autumn.

But when the image is flipped over, the reflection of the image in the water, it's daylight.

How? What's going on?

It took us a while to figure it out, can you?

Okay...okay...we'll help you. If you look towards the line of trees on the edge of the water, it might give you a clue.

"I flipped this photo upside down because the sand under the river kinda looked like stars - (turn your phone upside down)"he explained in the caption.

Once you're aware of what the 'stars' actually are - and you've got the photograph the correct way up - it's easy to see that the bright dots are actually grains of sand and pebbles underneath the surface of the water.

Amazing!