Astronauts on board the International Space Station took this detailed view of melt water pooled on the surface of iceberg A-39D, an iceberg measuring 2 km wide by 11 km long and currently drifting near South Georgia Island. The different intensities of blue are interpreted as different water depths. From the orientation of the iceberg, the deepest water (darkest blue) lies at the westernmost end of the iceberg. The water pools have formed from snowmelt—late January is the peak of summer in the Southern Hemisphere.
This iceberg was part of the original A-38 iceberg that calved from the Ronne Ice Shelf in October 1998. Originally the ice was between 200 and 350 meters thick. This piece of that iceberg is now probably about 150 meters thick, with around 15 m sticking up above the surface of the water.
This photograph was taken by astronauts looking south over the south Atlantic Ocean from the International Space Station on January 22, 2004. Another oblique view shows all three large remnant pieces of A-38 close to South Georgia Island.
More melt water had formed on the surface of the iceberg when the Moderate Resolution Imaging Spectroradiometer (MODIS) captured two additional images on February 7 and February 9, 2004. The false-color image from February 7 shows the entire top of the iceberg covered in a dark blue pool of liquid water in contrast to the bright blue ice.
Both photographs were taken from the International Space Station using a Kodak DCS760 digital camera and a 400-mm lens on January 6, 2004. ISS008-E-12555 was taken first, and ISS008-E-12564 was taken 2 minutes and 37 seconds later. Information provided by Ted Scambos, National Snow and Ice Data Center; image provided by the Earth Observations Laboratory, Johnson Space Center. The International Space Station Program supports the laboratory to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public, and to make those images freely available on the Internet. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC Gateway to Astronaut Photography of Earth.
