This is what our planet looks like from space at night: an unprecedented view
The Soumi NPP satellite had to make 312 orbits of Earth in order to achieve the data making up the composite global image
NASA’s explanatory video (in English)
This month, December 2012, NASA has given us a surprise by offering to the public images making up a new view of Earth by night. The satellite photographs bring together images of all the towns on Earth lit up at night time. In order to achieve this magnificent global view, the NASA Soumi NPP satellite had to make 312 orbits of the planet over nine days in April and thirteen days in October this year.
The space agency explains on its web page that many satellites are presently equipped to observe the Earth during the day when our planet is fully lit by the sun. However, a new sensor installed in the Soumi satellite, which was launched last year, has made it possible for scientists to observe Earth’s surface and atmosphere with this precision and clarity during both daytime and night-time hours.
Images from the NASA web page.
The sensor used is sensitive enough to detect even the light given off by a single ship at sea as well as auroras, forest fires, reflected moonlight and, of course, the artificial light generated by cities. “Unlike humans, the Earth never sleeps”, says Steve Miller, a researcher at the National Oceanic and Atmospheric Administration’s (NOAA) Colorado State University Cooperative Institute for Research in the Atmosphere. “For all the reasons that we need to see Earth during the day, we also need to see Earth at night.”
This beautiful composite nocturnal image of the planet has been achieved thanks to the technique of cloud-free images developed by NOAA and NASA scientists. The images were made possible by the satellite’s Visible Infrared Imaging Radiometer Suite, which detects light in a wide range of wavelengths.