Unusual movement of unusually lit craft over Iowa farm field.My friend and I stepped out on the deck to have a smoke when we noticed a strange moving object in the sky. It had red and green rotating lights as if either the craft was rotating itself or the lights were moving around the craft (clockwise motion). Now I AM aware that all small planes have green and red lights, but the way this thing was moving really threw us off... enough that I ran inside and woke up my wife. The object appeared to be hovering in one spot but once in a while would get kind of shifty, as if as if it were banking hard side to side, and when it would do this it would expose the bottom of what we believed to be either a disc shape or a mushroom shaped craft, either way the bottom was lit up yellowish, about the color of like a street light. Around the craft there was a very faint green glow to it. The craft hovered for about 30 mins. or so and slowly moved away from us. Both my friend and I are chefs at a local restaurant, and my wife! is a waitress, we are by no means experts on air crafts, but I have seen many planes in the night sky and this was not a plane. Its movements were strange ... it moved up and down very quickly with a curvy pattern simular to an "s". I am sorry that is the best way to describe its movements with out being abale to show you. Ufo, i don't know for sure. Airplane - NO. Either way I was wondering if anyone else saw this??? We tried to take pictures but our camera wasn't able to pick up the lights... we tried all of our phones with no luck and then we ran inside to grab our camera (fujifilm finepixZ5) not the greatest camera but we tried anyway... no luck. Just at the end of us watching this craft hover above what would have been a farm field, there was what appeared to be a falling star, if that has any relivence. The time was 12am on the nuts the object appeared in the sky slightly southwest of Floyd, IA. There wasn't a cloud in sky and just before the craft disappeared! there was a thunder like sound.