It's been said that we know more about the heavens above than we do about the deep sea here on Earth. Take a look at this creature and you might have a hard time guessing if it was filmed by a submersible or a spacecraft.

The footage was captured by a ROV (remotely operated vehicle) in the Perdido region of Alaminos Canyon in the Gulf of Mexico back in 2007 as it roamed nearly 8,000 feet below the surface. It shows a terrifyingly large creature, which looks like an extraterrestrial from an alien invasion movie, seemingly peering right into the camera. The camera pans nervously to the left, to the right, up and down, to reveal that the beast is dragging several very long tendril-looking appendages along with it.

You can view the footage for yourself above:

So what the heck is this thing? An alien? A mutant jellyfish? A nightmare? Researchers have identified it as a Magnapinna squid, also known as a bigfin squid. Because these creatures live in such deep waters, little is known about them, but you can learn more details about their characteristics on the Encyclopedia of Life. They are as mysterious as they are odd. No one has captured an adult specimen alive.

Ones that have been examined (dead specimens or from a few other deep sea videos like this one) they appear distinct from all previously known squid species. Some researchers have speculated that the creatures could be related to the long-extinct belemnites, an ancient line of cephalopods that existed during the Mesozoic era. If true, that could make them living fossils.

Bigfin squid are so elusive that nothing is known about their behavior. What do they eat? How do they mate? Their long, drifting tentacles offer hints about how they capture prey, perhaps by dragging them along the seafloor and snatching up anything unfortunate enough to get tangled up. Really, it's anybody's guess.

Since cephalopods as a group are widely recognized as among the most intelligent invertebrates on the planet, one has to also wonder about the cognitive capacity of this monster. Perhaps it's best to just stay out of the ocean entirely.