An enormous iceberg with an area about eight times the size of Manhattan has broken off an Antarctic glacier.

A huge crack along the surface of Pine Island Glacier (PIG), the longest and fastest shrinking glacier in the Antarctic, finally spread completely across the glacier's surface, creating the 278 square mile (720 sq km) iceberg. Scientists had suspected such a thing would occur since 2011 when they first noticed the crack. Confirmation that the iceberg had broken off the glacier was made Monday by the German TerraSAR-X satellite, according to the BBC.

"The main iceberg that calved from the flowing part of the glacier is almost as big as Hamburg," said Angelika Humbert, an ice researcher at the Alfred Wegener Institute in Bremerhaven, Germany. 

A Twitter account for the Pine Island Glacier made some quips when the iceberg broke off.  

"I'm great. Thanks for asking. Just a healthy natural event, like a snake shedding skin."

Very large icebergs are known to break off from the glacier every six- to 10 years, with notable events occurring in 2007 and 2001, the BBC reported, adding that the iceberg is not thought to be a result of global warming.  However, the glacier is still the source of about 10 percent of all the ice flowing off the western part of Antarctica.

"The PIG is the most rapidly shrinking glacier on the planet," David Vaughan from the British Antarctic Survey said to the BBC.

"It's losing more ice than any other glacier on the planet, and it's contributing to sea level rise faster than any other glacier on the planet. That makes it worthy of study.

In addition to the huge iceberg, a smaller "brother" iceberg also split fromt the glacier as a result of the calving.