A mysterious, massive and very, very strange 'snake shaped' object has been caught on radar off the coast of Australia.

The "phenomenon" was captured by the Bureau of Meteorology on 12 February near to Perth.

For hours speculation online ran rampant, with nobody apparently able to explain what the shape really was.

The weather office said it was definitely not caused by a cloud or rain, and there was no other strange weather in the area - or, for that matter, a mountain-range sized sky snake.

wa bureau of meteorology

Eventually the shape was nicknamed "#RottNessMonster" and social media users had fun trying to call the monster to heel.

"I, for one, welcome our new giant sea serpent overlords," Perth Sunrise Prints said on Twitter.

But in the end the shape did turn out to have a prosaic explanation, albeit still a fairly mysterious one.

ABC said that the Department of Defense had owned up to creating the shape after a military exercise involving ships and aircraft.

"The environmental conditions over the West Australian coast at the time of the activity provided a unique opportunity for this routine activity to be visible on the weather radar display," a spokesman told ABC.

"This exercise is ongoing."

Loading Slideshow...
  • 1. The Caged Graves

    Protection from grave robbers, especially medical students, is the reason most commonly suggested for the cages over two graves near Catawissa, Pennsylvania. But why would these women—sisters-in-law who died within days of one another in a remote mountain town—be targeted? Why did only these two graves need protection? Was it because of who they were, or how they died? And why was such a permanent solution needed for what was, presumably, only a temporary danger?

  • 2. The Fox Sisters

    In 1848, these teenage sisters claimed to be in communication with the ghost of a man buried beneath their house in Hydesville, New York. The ghost conveyed his messages through disembodied rapping sounds, and the girls went on to become famous spirit mediums. Their confession of fraud, bought and paid for when they were middle-aged and destitute, never fully explained the rapping or the source of their other-worldly knowledge. It especially didn’t explain the skeleton found behind a wall in the cellar of the Hydesville house years after the girls died.

  • 3. Teotihuacan

    Outside Mexico City lie the ruins of a civilization that supported 200,000 people back when London was just a Roman fort. Three pyramids, aligned in the same relative positions as the Pyramids of Giza, rise above an interlocking system of reflecting pools. Seen from above, the city design eerily resembles a computer’s circuit board, with the pyramids in the position of processing chips. An underground tunnel partially lined with mica (a heat sink and electrical insulator) connects two of the pyramids. This amazing city complex was constructed by people using only stone tools, according to archeologists. The Aztecs, who rose to power 700 years after this city was abandoned, didn’t know who lived here but believed they had supernatural powers. The Aztecs called the place Teotihuacan, <em>City of the Gods.</em>

  • 4. Coral Castle

    In 1923, a Latvian recluse named Edward Leedskalnin (reportedly 5 feet tall and about 100 pounds) began building a complex structure of stone on property in Florida. Working alone, at night, and unseen, Leedskalnin assembled his “rock garden” out of megalithic stones weighing on average 14 tons apiece. Neighbors saw neither heavy equipment nor any workers enter or leave the property. When asked how he moved the mammoth stones, Leedskalnin claimed to have rediscovered the secrets of the ancient pyramids. “It’s not difficult if you know how,” he said.

  • 5. Ambrose Bierce

    Author and war hero Ambrose Bierce is probably more famous for his disappearance than his writing. In 1913, Bierce wrote that he was traveling to Mexico “with a pretty definite purpose which is not at present disclosable” and vanished off the face of the earth. The logical explanation is that he ran afoul of soldiers in the Mexican Revolution. However, prior to this trip Bierce had been researching disappearances: men who vanished in fields in plain sight of their families, rooms within houses that swallowed up entire families, and one teenage boy whose tracks in the snow stopped mysteriously and whose mother heard his voice calling for help in that spot for years afterward. Bierce theorized that people could fall into dimensional holes and be trapped forever, suspended between life and death. When Bierce entered Mexico, he had a journalistic interest in both war and dimensional holes. One has to wonder which one got him.

  • 6. Tesla’s Lost Inventions

    Nikola Tesla was one of the most prolific inventors of the late 19th and early 20th centuries. The alternating current generator, radio, x-rays, the remote control, the laser, and the electron microscope all originated with Tesla’s research. A lot of his work still escapes our understanding—like the 7-inch oscillating box that nearly reduced a building to rubble and an electric generator that required no fuel, drawing free energy from cosmic rays. The 200 foot tower Tesla built on Long Island was supposed to be the first step in broadcasting free wireless electricity to the world. So, why did investors pull their funding on his projects? Why did the government demolish the tower, calling it a national security risk, and confiscate the inventor’s files after his death? And if Tesla was a man ahead of his time, why haven’t we caught up with him yet?

  • 7. Sego Canyon Petroglyphs

    This artwork, chipped and painted into the sandstone cliffs of Sego Canyon, some of it thousands of years old, supposedly depicts the religious visions of indigenous Native American cave dwellers. The armless figures, with over-large eyes, antennae, and helmet-shaped heads are explained by anthropologists as the imaginings of shamans or ritual costumes. But can anyone look at these drawings and NOT think of aliens? And why are they so similar to rock drawings in the African Sahara and Australia, also several thousand years old?