I saw this one evening just at dusk. I was walking a sick 100 pound dog that I was caring for who had gout and couldn't walk to do his business. I did this for about a month, 3 times a day, and on this eve, as it approached, I thought it was a huge dragonfly. It flew about 20 or so above my house. As it passed by, the entire tail lit up with multiple vivid plasma like colors that seemed to be like liquid and electric at the same time.