Forget space, there’s an unknown tundra right here on Earth: the sea. About 71% of our planet is made up of ocean and only 5% of those oceans have been explored. Startlingly enough, that means more than half of our planet hasn’t been explored.

Fascinating? Yes. Terrifying? Absolutely.

That being said, it shouldn’t be surprising that there are a lot of things we don’t know lurking in the depths of the ocean. And when we’re confronted with those mysteries, they’re understandably difficult to explain. This carcass is one of those mysteries.

In May of 2017, a 50-foot sea creature of unknown origins washed onto the shore of Seram Island in Indonesia’s Maluku province. The carcass immediately threw the residents of the island into a panic (can you honestly blame them?) and local authorities didn’t know what to make of the discovery.

Asrul Tuanakota, a 37-year-old fisherman on Seram, initially thought he had discovered a boat stranded in shallow water, according to the Jakarta Globe. Upon closer inspection, he determined that it was the rotting corpse of a dead sea creature that was seeping blood into the water. His initial reaction was that he had found a giant squid, based on what looked like tentacles found in the remains.

The creature was photographed and circulated the web within hours, where it would go on to boggle basically the entire Internet, including marine scientists worldwide.

George Leonard, the chief scientist at the Ocean Conservancy, told HuffPost that the rotting carcass was probably a baleen whale, judging by parts of a protruding skeleton and what appear to be baleen plates used to filter out food.

It’s likely that gases expelled during decomposition caused the carcass to become bloated and misshapen, and also contributed to the terrible smell that lingered for some days after the discovery. We don’t even want to picture that.

Seram is near the migration routes for baleen whales, so it makes sense that one would be nearby. According to Live Science, dead whales usually sink to the bottom of the ocean where bottom dwellers consume them. Gruesome, but not quite as gruesome as the bloody sight that washed ashore Seram. Experts have theorized that the whale had a bacterial infection that produced more gases or that it possibly died in warm waters, allowing bacteria to accumulate and gases to expand its body.

Others have agreed with Tuanakota’s initial reaction that what he found was a rotting giant squid. Still others have theorized that the corpse is neither of those species and something entirely different —maybe something that hasn’t been officially discovered yet.

Whatever the creature actually is, it’s still a pretty shocking sight. It can’t help but spur our imaginations and wonder what exactly could be at the bottom of the ocean, still undiscovered by human life. What do you think? Do you think this mysterious carcass is a whale, squid, or something very different? Make sure to share your thoughts with us!