Arctic Blob Mystery Solved

A mystery blob in the Arctic sea first described as "thick and dark and gooey" is, as scientists initially figured, biological.

Indeed, the blob was not oil, tests revealed. It was a massive bloom of algae, similar to those that affect the Northeastern U.S. coast and the Gulf Coast, Time magazine reports.

One scientist said algae blooms like this are not unknown in Arctic waters, describing the conditions that precede them as something "like a swimming pool that hasn't been cleaned in a while." Some algae blooms are toxic, making fish inedible; so far officials don't think this one is.

In the Gulf of Mexico, blooms of phytoplankton, a type of algae, can become so prolific they rob the sea of oxygen, creating a dead zone where fish and other creatures can't survive.