It seems like a day does not go by without at least one new UFO video appearing on YouTube. And it's not surprising, given all the cameras so easily within reach of so many people around the world.
Do these allegedly unexplained objects stand up to expert scrutiny? Is it possible that, among the thousands of videos taken by people, maybe there's one "smoking gun" UFO that's really from another planet?
The Huffington Post examined a few recent YouTube video posts and sent them to an expert for analysis.
This video of lights moving over a field near a Texas farm on the night of May 15, 2012 was posted by the user ShadoXAV.
In the video the lights seem to move slowly above the treeline, then below the trees. ShadoXAV also compared a daytime image of the trees with frames of the nighttime video, in an attempt to show how the unexplained lights were too high in the sky to be harvester combines.
"The Texas video shows a nice little image analysis, but what they failed to do, to my satisfaction, is make their case," said Marc Dantonio, chief photo and video analyst for the Mutual UFO Network.
"It seems clear that these [UFOs] were above the horizon from the vantage point of the control photograph they were using," said Dantonio, who has contracts with the U.S. Navy, Congress and the Joint Chiefs of Staff in Washington and creates special effects for television channels.
The Texas UFO footage could have been of harvester combines and possibly videotaped from a higher elevation point above the ground, Dantonio told The Huffington Post. "That control photo, while taken on the ground, superimposed with the video taken from a higher angle, is going to show ground objects looking like they were in the sky. I looked up harvester combines and guess what? They have multiple lights horizontally across them. If I saw it at night, that would look almost exactly like what I'm seeing in this video."
The next video, posted on June 19, 2012, by YNETGLOBALMEDIA, is from a Russian city.
An odd-shaped UFO is shown moving above the city and appearing to have numerous flashing lights around its perimeter.
"In this video, I saw alternating lights, one side to another, like an aircraft," said Dantonio. "It's certainly not moving at any odd speed. As it zooms in, the lens does some weird things with the light, but I can see the dark shape of the object," he added.
"The lights on each side of it are what could be called aircraft strobes, and this is the kind of thing you wouldn't expect to see on a UFO," Dantonio said. "I'm seeing what would be consistent with aircraft lighting and I see a possible wing, fuselage and a tail."
"While I don't disagree that it looks odd, it's not jumping out [at] me as something that we should label as an extraterrestrial craft -- not yet," he said.
Another Russian video, shot over Moscow on May 2, 2012, was posted by olegen77.
"It looks like the same craft from the previous video, as if somebody else caught the same one," Dantonio suggested. "It could be an aircraft that was being tested or flown around, and it certainly wasn't trying to hide or moving at an extraordinary speed. And it's hard to determine its distance."
Dantonio speculated that the object in this video may even have been a radio-controlled aircraft with lights on it that was flown by someone at night. Last year, he created such a craft for a National Geographic special, "The Truth Behind: UFOs."
One common factor is shared by these three videos and just about every videotape or photograph of a UFO at night: lights.
"There isn't any reason why they should illuminate themselves or even have flashing lights," Dantonio said. "We put flashing lights on flying objects so they don't hit each other; it's for navigational safety. But UFOs don't follow the same tenets that we follow."
Said Dantonio: "This is anthropomorphizing, where you apply a human characteristic to an unknown object."
Humans put lights on almost all types of vehicles, including planes, trains, automobiles, blimps and bicycles. On the other hand, if the objects result from an entity from very far away that does not require headlights, perhaps it's being done for human benefit, so people can better see them at night and take better, clearer pictures and videos.
Are these UFOs?