Leroy Vandervegt, a 50-year-old resident of Lafayette, a town roughly 25 miles north of Denver, shot the video Sunday evening after his 17-year-old son saw the glowing orbs move from southwest to southeast along the horizon.
"I don't know what they are," Vandervegt told the Boulder Daily Camera. "All I know is that I had no idea what it is. It wasn't a satellite, it wasn't an airplane and it wasn't a helicopter."
The paper reported that a Federal Aviation Administration official for the Rocky Mountain region noted that his staff did not notice radar returns reflecting any "abnormal unidentified activity within our airspace."
When Vandervegt saw what he described as "UFOs," he told his son to run inside and get a camera so they could film this murky mystery. By Friday, five days after posting, more than 39,000 YouTube visitors had viewed the phenomena.
As appealing as it is for many of us to speculate that we are not alone, Adam Frank, an astrophysicist blogging at NPR, questions why a planet-hopping spaceship would need headlights.
"Any civilization with technology capable of spanning light-years ought to be able to hide themselves well enough to avoid detection from hairy apes with jet-planes like us," Frank writes.
"Of course, [the lights] might be their engines but a species crossing trillions of kilometers of empty space is not going to be using rockets. Hopefully they have some other kind of 'hyperdrive' or something cool. If so, they should be smart enough to stealth its exhaust (does hyperdrive have exhaust?)."
Read more at the Boulder Daily Camera and NPR.
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