The Earth at Night

The Night Earth map is a fascinating tool that allows us to explore our planet’s light pollution in a unique and informative way. It provides a stunning view of the Earth’s surface, showing the lights that are visible at night and highlighting the areas that are the brightest and most urbanized.

One of the most striking features of the Night Earth map is how it showcases the differences in urbanization and population density across different regions of the world. While western Europe appears to be one of the brightest areas on the map, it is interesting to note that it may not necessarily be the most populated when compared to countries like China and India.

Cities tend to grow along coastlines and transportation networks, and this is reflected in the Night Earth map. For example, the United States interstate highway system is visible as a lattice connecting the brighter dots of city centers, while in Russia, the Trans-Siberian railroad appears as a thin line stretching from Moscow through the center of Asia to Vladivostok.

The Nile River, from the Aswan Dam to the Mediterranean Sea, is another bright thread that stands out in an otherwise dark region. It is fascinating to observe how this river has been a vital source of life and civilization for thousands of years, and its significance is clearly visible on the Night Earth map.

However, there are still regions on our planet that remain thinly populated and unlit. Antarctica, for example, is entirely dark, and exploring this region on the Night Earth map gives us a glimpse into its isolation and otherworldly beauty. The interior jungles of Africa and South America are mostly dark as well, highlighting the challenges that people in these regions face in accessing electricity and infrastructure.

Similarly, deserts in Africa, Arabia, Australia, Mongolia, and the United States are poorly lit, except along the coast and rivers. The boreal forests of Canada and Russia, and the great mountains of the Himalaya are also less illuminated, providing us with a clear view of the remote and rugged terrains that these regions offer.

Overall, the Night Earth map is a captivating tool that allows us to explore and understand our planet’s light pollution. It highlights the differences in urbanization and population density across different regions of the world and gives us a glimpse into the unlit and remote areas that remain unexplored. The map is not just an informative tool, but also an aesthetically pleasing one, showcasing the beauty of our planet from a unique perspective.

The Night Map

Two versions of the images are available:

• The main image of the Earth at night (2012) was captured by NASA using the Suomi National Polar-orbiting Partnership (Suomi NPP) satellite. It took over nine days in April 2012 and thirteen days in October 2012, during 312 orbits at 824 kilometers (512 miles) to capture the whole Earth. This satellite uses the “day-night band” of the Visible Infrared Imaging Radiometer Suite (VIIRS), which detects light in a range of wavelengths from green to near-infrared and uses filtering techniques to observe dim signals such as gas flares, auroras, wildfires, city lights, and reflected moonlight.
• The original image from 2000 was created by NASA using data from the Defense Meteorological Satellite Program (DMSP)’s Operational Linescan System (OLS), originally designed to view clouds by moonlight.

While the original image consisted of 87.970 images, the map from 2012 comprises 349.525 images, therefore adding a grand total of 437.495 images for this map.

The detailed images of the cities were taken by astronauts aboard the International Space Station. These have been obtained from the Image Science and Analysis Laboratory, NASA-Johnson Space Center. “The Gateway to Astronaut Photography of Earth”.

Further information can be obtained from the Earth Observatory article Bright Lights, Big City, and NASA’s Visible Earth website.

The daylight images provided by Google Maps (maps and satellite views) are also available for reference. The Google Maps API was used for creating the original visualisation.

Technology

The 3D map was created using Cesium via OpenLayers and ol-cesium. This uses imagery from OpenStreetMap, Thunderforest, Bing Maps, and Mapquest.

Geocoding is provided by Nominatim via ol3-geocoder.

As the maps provided by NASA were in a different projection as the one required by Google Maps, the GDAL – Geospatial Data Abstraction Library library was used for the conversion.

The Aurora Borealis and Aurora Australis (Northern Lights and Southern Lights) data is provided by NOAA – National Oceanic and Atmospheric Administration.

The clouds layer is provided by OpenWeatherMap.