Covering an estimated 5,800 sq km, the Larsen C ice shelf extends along the east coast of the Antarctic Peninsula from Cape Longing to Smith Peninsula.
The tweet described the iceberg as having split from the Larsen C ice shelf, or large blocks of ice connected to land but continue to float in the ocean.
Well here's something you don't see everyday: an iceberg so unbelievably geometric in shape you'd think it was deliberately carved with a big chainsaw.
A NASA spokesman said: "It will yield an unprecedented three-dimensional view of Arctic and Antarctic ice sheets, ice shelves and sea ice".
The US space agency's explanation that the odd-looking iceberg's sharp angles and flat surface was an indication that it had recently broken off from a larger iceberg didn't seem to cut it online.
NASA ice scientist Kelly Brunt said Tabular icebergs come about via a process "a bit like a fingernail growing too long and cracking off at the end".
"We get two types of icebergs: We get the type that everyone can envision in their head that sank the Titanic, and they look like prisms or triangles at the surface and you know they have a insane subsurface".
These are flat and long and form by splitting away from the edges of ice shelves.
"What makes this one a bit unusual is that it looks nearly like a square", she said.
As for the size of the iceberg NASA photographed, Brunt said it's possibly more than a mile across - but it hasn't been measured yet.
"Sea ice conditions have kept a lot of them near Bawden Ice Rise".