The view from your app

Last night marked 167 years since the planet Neptune was first observed from the Berlin Observatory, within 1° of where Urbain Le Verrier had predicted it would be. I recently took a photo of the sky from the crossing of Friedrichstraße and Unter den Linden (which is close to the site of the original Berlin Observatory, but about about 2 km from the location where Neptune was observed). Here's the sky over Berlin today:

Night sky over central Berlin by Christopher Kyba
is licensed under a Creative Commons Attribution 3.0 Unported License.

For comparison, I used the same camera and same settings to take another image of the sky during a star party at Naturpark Westhavelland, 82 km from where the first image was taken. The sky over Berlin was probably only a little bit brighter than this when Neptune was discovered:

Night sky over Naturpark Westhavelland by Christopher Kyba
is licensed under a Creative Commons Attribution 3.0 Unported License.

By 1913 the Berlin Observatory was forced to move outside of the city for three reasons: increasing light pollution, air pollution (aerosols), and shaking of the instruments caused by the passing of the nearby S-bahn trains. Researchers still work the Leibniz-Institut für Astrophysik Potsdam (as the Berlin Observatory is known today), but they generally no longer make optical observations at the site due both to the skyglow of Berlin and our area's tendency to inclement weather.

Neptune is quite bright, so it should still be possible to observe it from the center of Berlin today with binoculars, as long as you know where to look. Thanks to Axel Schwope from Leibniz-Institut für Astrophysik Potsdam for telling me about the history of Berlin Observatory yesterday.