The brightness of the full Moon was striking enough to distract Dan Khen (Member 65,792) from a firework display over the Puget Sound, north of Seattle, Washington State, US. ‘The light reflecting from the Moon was so intense,’ he told us, ‘that it almost looked like it hung in the sky in front of the clouds. (I assure you it was in fact behind them, where it should be!)’

Stratocumulus translucidus are low, lumpy clouds that cover parts of the sky but let sunlight or moonlight shine through. They are called translucidus because they’re thin enough for light to pass through. And where the moonlight shone through the edges of this formation, it bent, or diffracted, around the cloud’s tiny droplets to form subtle hues known as cloud iridescence. As Dan discovered, nature’s own light displays, though rarely performed with a bang, often outshine manmade pyrotechnics.