Orange line turned into green oval

I was smoking outside at night with three friends. I'm in the army stationed at fort bliss. We are training out in New Mexico at a site called tactical site 19 on McGregor range. Looking north, I noticed behind one of my friends this orangish line that grew slightly brighter by the second. I ask them what is that?" My three friends then turned and looked and we were all stunned. I took out my phone immediately and began to film it. Unfortunately there was to much light coming from the city to get a good video of it. The orangish line began to slowly drift to the right and faded into a light green color. At the same time it was changing colors, an oval shape started to form. My friends and I could not believe our eyes. Approximately 20 to 30 seconds into the initial encounter, the greenish ring grew incredibly fast, almost as if it had gotten a lot closer to us. As it grew, I then noticed it started to dim and grew immensely brighter. There was almost an aura or force field around it. It dimmed down again and suddenly vanished into thin air like nothing was ever there. Like it went invisible or something. It didn't make a single sound the entire time. I am absolutely positive that this was NOT man-made. I initially thought it was a shooting star but moved entirely to slow. I am very shocked and will not be forgetting about this for the rest of my life.