When it comes to the strange phenomenon of Unidentified Flying Objects (UFOs) there appear to be three general explanatory hypotheses offered, and all of them have their strengths and weaknesses.
First, UFO skeptics often affirm what might be called the "misidentified hypothesis" (MIH). This position insists that all UFOs are merely natural phenomena of some kind (misidentified natural or man-made phenomena, the results of false mechanical images, hoaxes, purely subjective psychological experiences, or some combination thereof). Those who embrace this position typically reason that since most UFOs inevitably become IFOs (Identified Flying Objects), those UFO reports that remain unresolved are just yet to be explained (but inevitably will have a purely natural explanation).
The clear strength of MIH is that it is factually true that the vast majority of UFO reports have purely natural explanations. Therefore this hypothesis doesn't necessitate positing any extraordinary explanation for UFO phenomena. However, the problem with this viewpoint is that it presumes what it should prove and therefore fails to genuinely account for all the data. Some UFO reports (though a small percentage) consistently defy purely naturalistic explanations even when examined by the most objective UFO researchers.
Second, the most popular theory among the general public for explaining UFOs is called the "extraterrestrial hypothesis" (ETH). This position proposes that some UFOs are actually metallic spacecrafts that are piloted by interplanetary space visitors. These space aliens represent what is thought to be a vastly advanced civilization that is presently studying mankind and will, eventually, make contact with humanity.
The strength of this hypothesis is that some UFO phenomena (though again a very small percentage) are difficult to explain naturally and have had some physical effects connected to them. However, due to serious scientific, technological, and logical problems most credible ufologists reject this theory. For example, it would seem to be physically impossible for spacecrafts to travel the vast distances of interstellar space in the amount of time available. Also, if UFOs are physical objects, they could not maneuver in the ways reported "such as making sharp, sudden turns and gyrations" without violating the laws of physics (which are reasonably presumed to be uniform throughout the universe).
Third, "the Interdimensional Hypothesis" (IDH) asserts that UFOs are real and may exhibit physical effects, but they are highly deceptive and actually belong to another dimension of reality beyond our time-space continuum. Some Christian ufologists believe that some UFO phenomena are real, not physical, deceptive, anti-Christian in expression, and potentially malevolent (conceivably reflecting a demonic influence).
The strength of this position is that it does seem to account for what appear to be paranormal characteristics sometimes associated with UFOs. However, the weakness lies in the fact that the paranormal/occult hypothesis may suffer from excessive complexity, general vagueness, and heightened speculation.
While this writer thinks that the IDH has some interesting and conceivably powerful explanatory power in conjunction with some UFO phenomena, it is nevertheless prudent to be cautious about drawing any hard and fast conclusions about ultimate explanations concerning the UFO phenomenon.
For further studies concerning the bizarre world of UFOs, see Hugh Ross, Kenneth Samples, and Mark Clark, Lights in the Sky and Little Green Men: A Rational Christian Look at UFOs and Extraterrestrials (Colorado Springs: Navpress, 2002).