Sky serpents are UFOs that have been sighted very often in the 20th and 21st century.
They are considered to be phantoms as there isn't really any physical way they could exist. After all, what living creature could look like a snake but manage to float around independently?
These creatures are studied more often in Parapsychology (study of the paranormal) than in Cryptozoology. However, these two studies are loosely connected, so I'm including them in this blog.
Other explanations include that they are really alien crafts designed to (unsuccessfully) desguise themselves, or that they are oriental dragons. Other than this cryptozoologists aren't very interested in them.
The sightings people come up with are actually quite stunning though.
Ghost or dragon?