Flying over the Philippine Sea, an astronaut looked toward the horizon from the International Space Station and shot this photograph of threedimensional clouds, the thin blue envelope of the atmosphere, and the blackness of space. The late afternoon sunlight brightens a broad swath of the sea surface on the right side of the image. In the distance, a wide layer of clouds mostly obscures the northern Philippine islands.
Looking toward the sun to capture an image is a special technique used by astronauts to accentuate the three dimensions of landscapes and cloudscapes through the use of shadows. Two large thunderclouds rise next to one another (lower right). These clouds have long tails, also known as anvils, which stretch nearly 100 kilometres to the south. Anvils form when thunderstorm clouds rise high into the atmosphere and reach a “capping layer” thousands of meters (tens of thousands of feet) above sea level. Capping layers stop the upward growth of a cloud, deflecting air currents horizontally to form anvils.
Astronaut photograph ISS048-E-10018 was acquired on 25 June 2016, with a Nikon D4 digital camera using a 116 millimetre lens, and is provided by the ISS Crew Earth Observations Facility and the Earth Science and Remote Sensing Unit, Johnson Space Center. The image was taken by a member of the Expedition 48 crew. The image has been cropped and enhanced to improve contrast, and lens artefacts have been removed.