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Last week, NASA
tweeted a photo of a perfectly natural and rectangular iceberg spotted during a flyover of the northern Antarctic Peninsula.
The unusual image blew up online and now NASA is back with more photos of weirdly angular icebergs from the same
Operation IceBridge trip.
From yesterday's #IceBridge flight: A tabular iceberg can be seen on the right, floating among sea ice just off of the Larsen C ice shelf. The iceberg's sharp angles and flat surface indicate that it probably recently calved from the ice shelf. pic.twitter.com/XhgTrf642Z
— NASA Ice (@NASA_ICE) October 17, 2018
We usually think of icebergs as craggy chunks like the one from Titanic, but IceBridge senior support scientist Jeremy Harbeck caused a stir after he captured photos of the flat, sharp-cornered specimens.
“I thought it was pretty interesting; I often see icebergs with relatively straight edges, but I’ve not really seen one before with two corners at such right angles like this one had,” Harbeck said in a
NASA post.
This panorama of the entire tabular iceberg was edited together from two images taken while flying past the berg.NASA/Jeremy Harbeck
These nature-made frozen slabs have an official name: “tabular icebergs.” Because of its smooth surface and clean edges, the rectangular berg likely only recently broke off the
Larsen C ice shelf, which famously released a Delaware-sized chunk of ice last year, now dubbed A68.
“The iceberg’s sharp angles and flat surface indicate that it probably recently calved from the ice shelf,” NASA
tweeted.
In the new photo (at the top of this article), Harbeck captured a slightly less rectangular iceberg around the same area. Look closely and you can see a corner of the now-classic rectangular iceberg as well as A68 in the distance.
“I was actually more interested in capturing the A68 iceberg that we were about to fly over, but I thought this rectangular iceberg was visually interesting and fairly photogenic, so on a lark, I just took a couple photos,” Harbeck added in the NASA post.
Massive Iceberg Finally Breaks Off: #Antarctic Landscape 'Changed Forever' https://t.co/S5KiGgMJ86 @greenpeaceusa @Greenpeace @MIDASOnIce
— EcoWatch (@EcoWatch) July 12, 2017
These calving events are like a long fingernail that eventually snaps off at the end, University of Maryland Earth scientist Kelly Brunt explained to LiveScience.
Such a break can create nearly perfect geometric edges, similar to when a glass plate shatters and creates straight edges, sea ice specialist Alek Petty told NPR.
Operation IceBridge Mission Scientist John Sonntag explains more about the tabular icebergs. Watch here:
New #IceBridge video: Mission Scientist John Sonntag provides commentary on footage from an Oct. 16 flight over the tabular iceberg that became social media famous, plus bonus icebergs and the massive A68 berg. pic.twitter.com/8nkeSCsj4G
— NASA Ice (@NASA_ICE) October 24, 2018