UFO? Space debris? Fireball? Exactly what was in the skies over Oregon?

Residents of Portland, Oregon saw something strange in the sky on Wednesday morning, but there's still no word on exactly what it was.

Images of whatever it were posted on the Twitter account of KOMO News, showing what appeared to be something burning falling from the sky, leaving behind a smoke trail as it fell:

This video was shot by Mike Warner, a photojournalist who was in the KATU News helicopter at the time, showing at least the smoke trail or contrail.

According to KOMO News, U.S. Strategic Air Command verified that nothing man-made had fallen from orbit (space debris or otherwise), and there was some suggestion that it may have been a fireball meteor.

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However, for a fireball to leave behind a trail of smoke like that, it would have to be fairly big. That would have created a very bright flash in the sky that would have been noticed by many people.

There is a bright part to the 'trail' or cloud, of course. It's easily seen in the various photographs (click here to see them). However, comparing the video shot by Mike Warner to the photographs, he took that video earlier, just before the sun was rising, and there is no bright patch. The photographs are from later, after the sun is climbing above the horizon. That suggests that the bright spot is just sunlight shining through that part of the 'trail', which was probably thinner than the rest. The unusual 'twisted' look of the trail could just be from atmospheric turbulence.

In all likelihood, this was probably just a contrail from an aircraft, but it will be interesting to see if we can get a definite answer at some point.

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