Very Bright red and white circular object in southwest sky

I just entered on the I-17 freeway coming off of the 101 freeway and I was traveling southbound. I noticed up in the southwest sky an extremely bright circular object that was bright white in the center and had a reddish/orangish outer ring around it. The outer ring looked like it was on fire and or pulsating and not as clearly defined as the white inner circle. It was very large in comparison to the airplanes in the further background. I grabbed my phone and looked down for a second to click on the camera to record it, and when I looked up to recorded it, it was gone. Totally disappeared and was no where in the sky to be found. I have always been interested in what is beyond the stars, so if there is any other information from someone else reporting this object, I would like to hear about it as well. Thank you for listening.