1. The planet Venus
UFO reports go up when Venus makes a bright appearance in the night sky.
2. Meteors, comets, and fireballs
3. Lenticular clouds
Known as alto cumulus standing lenticular clouds, these are stationary lens-shaped clouds at high altitudes. They occur normally where stable moist air flows over a mountain or a range of mountains.
4. Ball lightning
A sphere of static electricity that can glow for minutes. When seen during daylight, it may appear to be fluid, silvery-like, metallic and/or "disk-like."
At times when attracted to an object, a ball of lightening may appear to be 'following' that object such as a plane, matching its movements and therefore seemingly under intelligent control.
Commonly described as spherical, ovoid, teardrop, or rod-like in shape, and with various colors.
5. Weather Balloons
These balloons can be very large and are often coated in a reflective material. They can also fly at high altitudes with substantial speed. Winds may push them in different directions.
6. Satellites
Many satellites orbit the earth. They move fast and are highly reflective.
One surveillance network tracks more than 8,000 satellites. Frequently orbiting for years they are not an uncommon sights and may even seem to pulsate or "wink out."
7. Flares
Military aircraft often drop flares during night training. Such flares are quite large, burn brightly and are suspended from parachutes. Close together, these flares may look like running lights or "portholes."
This is an explanation for the supposed UFO lights reported over Phoenix, Arizona in 1997.
8. Birds, lens flare, reflections, and other abnormalities
Under certain circumstances birds flying at high altitudes, which can also be reflective when wet, appear to be metallic.
Bits of tin foil or corrugated metal pushed skyward by high winds and updrafts, falling chunks of ice from an airliner may also seem silvery and luminescent.
Cockpit lights reflecting off a canopy have been mistakenly identified as UFOs.
9. Aircraft
There are circumstances when aircraft appear unusually, such as a jet's landing lights diffused by thick fog or an aircraft flying through thick clouds on a dark night. An aircraft can seem static and motionless at times, until it turns.
Blimps, helicopters, and fixed wing planes capable of hovering, are other UFO explanations.
10. Experimental military aircraft
Note: This research was originally compiled by Jeff Danelek. Daniels is a Colorado author who writes about subjects such as the paranormal, spirituality and religion. To see his work visit www.ourcuriousworld.com
