Researchers have recently discovered that humans have a previously undiscovered extra set of salivary glands right inside our heads. Makes one wonder if there are any more seemingly obvious mystery organs we are yet to uncover. Because as you might know, we discovered what a clitoris looks like in the 2000s — seriously, you have to thank Helen O'Connel for that.

In this case, the "unknown entity" was discovered by an accident. A team of researchers was studying prostate cancer patients. They were utilizing a kind of advanced imaging method called PSMA PET/CT (prostate-specific membrane antigen positron emission tomography/computerized tomography ) — PSTA is a marker for prostate cancer. Although, this time, it marked something else too.