The science of weather is a fascinating one; but even more so are the flukes and irregularities that can occur within our world. This is a list of 20 of the most amazing and unusual of those anomalies.20Moon bowsA rainbow is caused by the Sun shining on moisture droplets, most commonly in a post-rain atmosphere. A moon bow is much rarer, only seen at night when the moon is low and full to almost full. One popular place to see moon bows is at Cumberland Falls in Kentucky, as pictured above.19Mira