What is Cities at Night?
Cities at Night is a citizen science project whose aim is to create a Google maps style map of the world using night photographs taken by astronauts onboard the ISS.
You would likely take over 300 pictures during a weekend in Paris, so imagine how many you would take if you were in space. This is what happens to the astronauts. Not only do they take hundreds of photographs where they carefully select the frame, focus and exposure, but sometimes they set their cameras to take pictures automatically while they work on their experiments.
NASA has a database with almost half a million pictures taken by the astronauts on the International Space Station. Organizing the pictures with a computer is non-viable. Computers need very complicated algorithms to interpret photographs.
The human eye knows right away if the camera was pointing at a city or just at the stars, which is why we created Cities at Night, a platform with 3 apps where anybody can help while looking through beautiful pictures taken from space.
Have you tried the 3 apps?
With this application you can help locating which one is the city in a picture.
Building the map
This is at the moment the best map of the Earth that exists. It was created with data from Suomi NPP Satellite using VIIRS (Visible Infrared Imaging Radiometer Suite) camera.
We are using color pictures with 10 times more resolution. While the images taken by VIIRS have a scale of about 750m per pixel, those obtained by astronauts aboard the International Space Station have a better resolution depending of the lens used, reaching 5 m/pixel.
All these maps let us know where the best stargazing places are located and where light is excessive and could be improved.
Scientific research documentation
Space agencies words