Saw a gigantic crescent moon shape object uncloak and disappear while moving in the nighttime sky.

I was at work taking the trash out to the dumpster at 9 pm when in the upper western region of the nighttime sky I saw what appeared to be a crescent moon shape object forming as it travelled south. As it slowly formed over 10 to 15 seconds it was a blurry whitish color and turned reddish hue as it became more defined then it disappeared from view. The size of the object was 2 to 4 times bigger than the moon which was almost full at the time coming over the mountains to the east.