Astronomy News

Landsat Look at B-44

You may remember the news of the huge ice berg that calved a few months ago in Antarctica called B-44. Now thanks to the southern sun and the Landsat 8 satellite we get a look at the area.

The polyna, although not the same reminded me of a phenomenon sometimes seen in larger freshwater lakes which is an internal seiche. A friend of mine ran a fish factory and had to deal with a seiche. Unlike what you may think of as a fish farm or fish hatchery you may visit and enjoy, this place was and is exactly like an industrial factory and is an all around horrible place. My friend only could take working there a short time and has moved on, but I do remember the headaches that seiche would cause.

Anyway, back to the topic, another fun fact about the image is that it was taken under the midnight sun. Here’s the original caption from NASA:
In September 2017, a new iceberg calved from Pine Island Glacier—one of the main outlets where the West Antarctic Ice Sheet flows into the ocean. Just weeks later, the berg named B-44 shattered into more than 20 fragments. On December 15, 2017, the Landsat 8 Earth-orbitng satellite took this image of the broken berg. An area of relatively warm water, known as a polyna, has kept the water ice free between the iceberg chunks and the glacier front. The polynya’s warm water could have caused the rapid breakup of B-44.

This image was acquired near midnight local time. Based on parameters including the azimuth of the Sun and its elevation above the horizon, as well as the length of the shadows, it is estimated that the iceberg rises about 49 meters above the water line. That would put the total thickness of the berg—above and below the water surface—at about 315 meters.

Image Credit: NASA