Cloudy Sulawesi

Cloudy Sulawesi

The International Space Station was crossing over the equator when an astronaut looked east and took this photograph just after sunrise. The strip of land outlined by morning sunglint is the northern peninsula of the Indonesian island of Sulawesi. The darker areas in the lower portion of the photo mark the edge of the day-night line, also known as the terminator.

Indonesia sits in a notoriously cloudy region of the globe. In the image foreground, clouds cast long shadows as the Sun’s rays strike at a low angle. Toward the horizon, clouds cast shorter shadows where the Sun is already higher in the sky.

Scientists who work with astronaut photos are well-practiced at identifying places on Earth through the perspective of an astronaut looking out from the ISS. However, consistently cloudy regions are more difficult to recognize. Sunglint helps by highlighting coastlines that are often obscured by clouds and aerosols. Yet those same clouds may have been exactly what inspired the astronaut to capture this scene.

Astronaut photograph ISS059-E-67875 was acquired on May 19, 2019, with a Nikon D5 digital camera using a 58 millimeter 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 59 crew. The image has been cropped and enhanced to improve contrast, and lens artifacts have been removed. The International Space Station Program supports the laboratory as part of the ISS National Lab 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. Caption by Andrea Meado, Jacobs Technology, JETS Contract at NASA-JSC.