Bright glowing object in the sky then began moving

As I was driving on the nj turnpike I noticed a plane that seemed to be traveling inland towards the Newark airport. I am aware that there are many aircrafts in this area due to all the airports, and aircrafts conducting security and even tourist flights. And I am also aware of what military and commercial airplanes and helicopters look like and which blinking lights each aircraft may have. But in this case, an airplane was flying inland as I started to explain before, I had seen a glowing yellowish light which I thought was part of the plane, until I realized the light stayed in one place as the plane continued east. The light began to get brighter and brighter and I was in disbelief, and then the light began traveling in the opposite direction from the plane and while doing so the light became dimmer and dimmer until it disappeared. I also saw a helicopter in a far distance, far from the light that I had witnessed and tried to correlate the two but there was no way it had came from the helicopter based on the trajectory and distance of the helicopter from which the light had vanished from. Most certainly a ufo.