If you have watched Spongebob Sqaurepants (like I had for many years during my childhood), then you may remember Goo Lagoon, the beach of Bikini Bottom.
But while we are still trying to find the famous krabby patty of the Krusty Krab, it seems that we actually DO have underwater beaches!
First discovered in 1990, these underwater lakes, as they are often referred as, are brine pools. Brine refers to water with an extremely high concentration of salt, about 5 times saltier than the surrounding seawater.
Brine pools are not be confused with brine lakes, which are more widely known. Examples of famous brine lakes include the Dead Sea or Great Salt Lake. If you were to pour an great amount of normal seawater over a brine lake, the result will be a brine pool.
As brine is denser than seawater, there is a clear line that separates brine pools from the overlaying seawater. In fact, it is so dense that trying to dive into the brine pool with a submersible vehicle is like punching jelly. The submersible vehicle will bump and can only float on the pool's surface while little ripples spread out from the impact. It will need to take a powerful submarine to penetrate the dense pool surface.
What makes a brine pool more "beach" than "lake" is its coastline, which is full of life - not something you would expect in the ocean abyss.
While a normal beach ecosystem is dependent on the raising of the Sun, a brine pool ecosystem is mainly supported by cold seep activity - which in this case is methane raising up from the seafloor.
This methane supports the methane eating bacteria, which in turn is a sustainable source of nutrients for the thousands of mussels that litter the sandy shore.
One can also find shrimps and polychate worms, many of which are unique to the environment, and this in turn attracts larger sea creatures, such as eels.
You can see this surreal environment in a cut of the National Geographic Documentary, The Deep.
This complex ecosystem is completely independent of our Sun, and supports the theory that Life can exist regardless of the environments.
Years after asking whether there is life outside of Earth, we have since refined the question to whether there is life as we know it outside of Earth.
With each new discovery and exploration within our planet, we find that life can triumph in the most barren and hostile environments. And with 99% of the seafloor still waiting to be explored, one can just imagine what form of life is out there - Just keep in mind, Mother Nature may have already thought of it.
Now if only we can find the Krusty Krabs...
For those who want more information, do head over to the National Oceanic and Atmospheric Administration website on Brine Pools.