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.
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."