Weird object in the sky in Las Vegas area - please help identify

On Thursday, December 06, 2012 my husband and I were on our way home from work and stopped in the Whitney Ranch area to pick up my niece. While we were waiting (at around 5:30 pm) my husband noticed something strange in the night sky almost directly above us. The object had been travelling rather fast from South to North when it came to a stop and hovered. This was the Southeast area of the Las Vegas valley. This area happens to lie directly in the flight path to McCarran airport so it’s not unusual to see aircraft. The object appeared to be a round sphere, glowing with pulsating red light. By the way it stopped and hovered we first thought it might be a helicopter at high altitude but it didn’t have the normal lights you’d expect to see on any known aircraft. It simply pulsated a glowing red light. At one point, the pulse was rather large and shortly after that there seemed to be a white halo above it for a brief moment. Immediately following this the object seemed to fly straight up very quickly. The light seemed to become more and more distant and turned a dim white color and we assumed it was heading straight up to a much higher altitude. This assumption proved incorrect however as we began driving (watching it through the sunroof) my fist impression was that it was taking off at a high speed. Then I realized it only seemed to be moving because we were moving. As we made turns through the neighborhood this continued which confirmed that it could not possibly be at the high altitude we thought it had climbed to. The light had become very faint and it was hardly discernible amid the stars, but as we traveled the stars seemed to stay stationary while this object was obviously very close to us in relation. It was higher than the incoming airplanes but I cannot judge the altitude. I would greatly appreciate everyone's input. I took photos with my Blackberry (which really stinks as a camera) and uploaded the full files here: [link to weirdobject.shutterfly.com] These photos can be downloaded from this site, so please examine them carefully!

Thank you GLP!!