On 1 March 2008 Envisat's Advanced Synthetic Aperture Radar (ASAR) instrument spotted a huge fissure running south to north through the massive A53A iceberg located just east of the South Georgia Island (visible at image bottom) in the southern Atlantic Ocean. ASAR is able to produce high-quality images of icebergs and ice sheets and is capable of differentiating between different types of ice because it is able to see through clouds and local darkness - conditions often found in polar areas.