We've seen reports of UFOs that turn out to be balloons, and others that are military aircraft, privately-owned drones, Chinese lanterns, even birds, insects and the planet Venus.
The mystery behind this UFO is a new one to us. But let's put it this way: If you were driving through the Catalina Mountains near Tucson earlier this summer, it could have been you.
Our story begins on the Fourth of July, when Roman candles and all sorts of fireworks are sometimes reported as UFOs. That wasn't the case here.
Two Arizona residents videotaped a colorful, changing display (see above) of an object that appeared to be in the sky above Sabino Canyon.
One of those men, Tom Sanger, focused his color night vision camera and captured (in the following video) several minutes of the reported motionless object over the Catalina Mountains.
In its initial chronicle of this UFO sighting, OpenMinds.TV seemed to step into the future, suggesting "Often cars driving on mountains can be mistaken for something more mysterious. [Their lights] usually go on and off as the cars pass behind trees."
If that were true, this Arizona report would fall into the category where most unexplained lights start off as UFOs (unidentified flying objects) and eventually become IFOs (identified flying objects).
Guess what? It's true.
When the Sabino Canyon story came out, Dennis Freyermuth -- who owns Sunburst Video, an Arizona film production company -- investigated the incident and came to the conclusion that the so-called unexplained lights were caused by "human activity" on a nearby mountain, according to OpenMinds.TV.
Freyermuth is also director of investigations for Phoenix MUFON, part of the larger Mutual UFO Network that investigates global UFO reports. He traveled to the site from where the original Tucson video was reportedly shot, made a new video and was able to closely match his video angle with the one Sanger videotaped on July 4.
The following remarkable dual matched up video -- comparing Freyermuth's to Sanger's original video -- clearly shows how the unusual lights in the dark that seem to be in the sky are, in fact, on the ground, on the mountain, and looking remarkably like the headlights of oncoming, human-made vehicles:
"After close review of the submitted video clips as evidence and comparing to our on-sight test sample photos and video, along with statements from the area park rangers, it is the conclusion of this lab evaluation that the submitted videos of anomalous lights is simply human activity at a lookout point located near the top of Mt. Bigelow where there is a covered shelter and three communication towers," Freyermuth told OpenMinds.TV.
While this was a great example of how most UFOs can be explained, that's not always the case, even in situations investigated by the military.
In 1969, the U.S. Air Force terminated Project Blue Book, its 22-year study of UFO reports. Of the nearly 13,000 sightings it investigated and solved, 5 percent were finally listed as unidentified. That percentage of unknowns continues today. Of course, it doesn't mean these sightings were ET visitations. It just means there's a lot going on in the sky that we can't easily explain.
One reason why it's important to accurately demonstrate the non-alien reality of most UFO stories is because so many people believe Earth has been visited by extraterrestrials.
A 2013 HuffPost/YouGov poll asked 1,000 adults if they either believed or didn't believe that some people have witnessed UFOs with an extraterrestrial origin. While 35 percent were skeptical that any UFOs may be alien-related, nearly half of adults surveyed (48 percent) resounded in the affirmative.
As America gears up to choose its next commander in chief, it's interesting to note that, in the ET believer camp, the 2013 poll revealed 58 percent are Democrats, 47 percent Independents and 37 percent Republicans.
Nearly all UFOs have a perfectly earthly explanation. But that doesn't mean there isn't a real ET close encounter waiting to emerge from our galactic neighborhood.
We just have to keep looking.