"Two Denver, CO, witnesses report watching a silent and slow-moving object move overhead with two lights and a "concave or crescent" shaped front end that was the size of a "football field" and seemed to be transparent, according to June 24, 2011, testimony from the Mutual UFO Network (MUFON) witness reporting database.

"As it approached nearly overhead of us, I could make out a faint shape on the 'front' between the lights," the reporting witness stated. "It was concave like a crescent or wave shape that was a hazy bluish-grey color. It really seemed to mimic the wispy clouds. It also moved in perfect alignment with both lights. I could not make out the 'back' of the craft. The hazy blue crescent just faded to black. From light to light the craft seemed the size of a football field."

The object moved slow and appeared to be low in the sky.

"It moved slow, silent, and steady with the lights in that alignment the entire time. It traveled about 1 mph, SW to NE, and seemed to be on a flight path, not unlike it was headed towards DIA, except that it was lower than one would expect (difficult to judge, but probably less than 400 yards above the trees, maybe around 200 yards)."

No images or videos were included with the MUFON report, which was filed on June 24, 2011. The incident occurred on May 30, 2011. The above quotes were edited for clarity."