Light pollution: the night sky of cities

At night, city lights brighten the sky and wash out the stars. Of 158 cities, the darkest sky is in Zermatt, the brightest in Riyadh. Mag/arcsec²: the bigger the number, the darker the sky (22 under a perfect sky).

City	Sky (mag/arcsec²)	Sky type	Visible stars	Milky Way
Riyadh	17.5	inner-city sky	150	no
Mexico City	17.5	inner-city sky	150	no
Moscow	17.5	inner-city sky	150	no
Bangkok	17.5	inner-city sky	150	no
São Paulo	17.5	inner-city sky	150	no
Shanghai	17.5	inner-city sky	150	no
Jakarta	17.5	inner-city sky	150	no
New Delhi	17.5	inner-city sky	150	no
Cairo	17.5	inner-city sky	150	no
Los Angeles	17.5	inner-city sky	160	no
Beijing	17.5	inner-city sky	160	no
Bangalore	17.5	inner-city sky	160	no
Tokyo	17.5	inner-city sky	160	no
Osaka	17.6	inner-city sky	160	no
Amman	17.6	inner-city sky	160	no
Seoul	17.6	inner-city sky	170	no
Doha	17.6	inner-city sky	170	no
Santiago	17.6	inner-city sky	170	no
Saint Petersburg	17.6	inner-city sky	170	no
Accra	17.6	inner-city sky	170	no
Jeddah	17.6	inner-city sky	170	no
Paris	17.6	inner-city sky	170	no
Kolkata	17.6	inner-city sky	170	no
Dubai	17.6	inner-city sky	170	no
Milan	17.6	inner-city sky	170	no
Mecca	17.6	inner-city sky	170	no
Madrid	17.7	inner-city sky	170	no
Johannesburg	17.7	inner-city sky	170	no
Denver	17.7	inner-city sky	180	no
Rome	17.7	inner-city sky	180	no
Athens	17.7	inner-city sky	180	no
London	17.7	inner-city sky	180	no
Montreal	17.7	inner-city sky	180	no
Buenos Aires	17.7	inner-city sky	180	no
New York	17.7	inner-city sky	190	no
Bogotá	17.7	inner-city sky	190	no
Mumbai	17.7	inner-city sky	190	no
Warsaw	17.7	inner-city sky	190	no
Brasília	17.7	inner-city sky	190	no
Jaipur	17.8	inner-city sky	190	no
Chennai	17.8	inner-city sky	200	no
Casablanca	17.8	inner-city sky	200	no
Chicago	17.8	inner-city sky	200	no
Singapore	17.8	inner-city sky	210	no
Algiers	17.8	inner-city sky	210	no
Tripoli	17.8	inner-city sky	210	no
Miami	17.8	inner-city sky	210	no
Melbourne	17.8	inner-city sky	210	no
Toronto	17.8	inner-city sky	210	no
Abidjan	17.8	inner-city sky	210	no
Nairobi	17.8	inner-city sky	210	no
Naples	17.8	inner-city sky	220	no
Istanbul	17.9	inner-city sky	220	no
Tunis	17.9	inner-city sky	220	no
Barcelona	17.9	inner-city sky	220	no
Brussels	17.9	inner-city sky	230	no
Lisbon	17.9	inner-city sky	230	no
Quito	17.9	inner-city sky	230	no
Valencia	17.9	inner-city sky	230	no
Stockholm	17.9	inner-city sky	230	no
Hong Kong	17.9	inner-city sky	230	no
Seville	17.9	inner-city sky	230	no
Quebec City	17.9	inner-city sky	230	no
Rio de Janeiro	17.9	inner-city sky	230	no
Benghazi	17.9	inner-city sky	240	no
Berlin	18.0	inner-city sky	240	no
Perth	18.0	inner-city sky	240	no
Prague	18.0	inner-city sky	250	no
Sapporo	18.0	inner-city sky	250	no
Tangier	18.0	inner-city sky	250	no
Lyon	18.0	inner-city sky	250	no
Zaragoza	18.0	inner-city sky	250	no
La Paz	18.0	inner-city sky	250	no
Fez	18.0	inner-city sky	250	no
Oran	18.0	inner-city sky	260	no
Dublin	18.0	inner-city sky	260	no
Brisbane	18.0	inner-city sky	260	no
Alexandria	18.0	inner-city sky	260	no
Amsterdam	18.0	inner-city sky	260	no
Porto	18.0	inner-city sky	260	no
Sydney	18.1	inner-city sky	260	no
Rabat	18.1	inner-city sky	270	no
Hamburg	18.1	inner-city sky	270	no
Cape Town	18.1	inner-city sky	270	no
Vienna	18.1	inner-city sky	270	no
Seattle	18.1	inner-city sky	280	no
Dakar	18.1	inner-city sky	280	no
Oslo	18.1	inner-city sky	280	no
Kyoto	18.1	inner-city sky	280	no
Kathmandu	18.1	inner-city sky	290	no
San Francisco	18.1	inner-city sky	290	no
Aswan	18.2	inner-city sky	290	no
Lima	18.2	inner-city sky	290	no
Marrakech	18.2	inner-city sky	290	no
Vancouver	18.2	inner-city sky	300	no
Frankfurt	18.2	inner-city sky	300	no
Beirut	18.2	inner-city sky	300	no
Bilbao	18.2	city sky	300	no
Malaga	18.2	city sky	310	no
Lagos	18.3	city sky	310	no
Toulouse	18.3	city sky	310	no
Luxor	18.3	city sky	310	no
Marseille	18.3	city sky	320	no
Bordeaux	18.3	city sky	320	no
Montpellier	18.3	city sky	320	no
Palma de Mallorca	18.3	city sky	320	no
Granada	18.3	city sky	320	no
Strasbourg	18.3	city sky	340	no
Perpignan	18.4	city sky	340	no
Toulon	18.4	city sky	350	no
Nice	18.4	city sky	360	no
Luxembourg	18.4	city sky	360	no
Lille	18.4	city sky	370	no
Geneva	18.4	city sky	370	no
Dijon	18.5	city sky	390	no
Cadiz	18.5	city sky	390	no
Munich	18.5	city sky	410	no
Zurich	18.5	city sky	410	no
Orléans	18.6	city sky	420	no
Tromsø	18.6	city sky	420	no
Pointe-à-Pitre	18.6	city sky	430	no
Le Havre	18.6	city sky	430	no
Auckland	18.6	city sky	440	no
Reims	18.7	city sky	470	no
Nantes	18.7	city sky	480	no
Saint-Étienne	18.7	city sky	480	no
Cayenne	18.7	city sky	480	no
Clermont-Ferrand	18.7	city sky	490	no
Edinburgh	18.8	city sky	500	no
Metz	18.8	city sky	500	no
Rennes	18.8	city sky	500	no
Fort-de-France	18.8	city sky	510	no
Limoges	18.8	city sky	510	no
Nîmes	18.8	city sky	540	no
Nancy	18.9	city sky	540	no
Reykjavik	18.9	city sky	550	no
Tours	18.9	city sky	560	no
Rouen	18.9	city sky	560	no
Lausanne	18.9	city sky	570	no
Venice	19.0	city sky	620	no
Monaco	19.0	city sky	620	no
Grenoble	19.0	city sky	640	no
Nouméa	19.1	city sky	660	no
Angers	19.1	city sky	680	no
Innsbruck	19.2	city sky	710	no
Dunedin	19.2	city sky	720	no
Ajaccio	19.2	suburban sky	740	no
Annecy	19.2	suburban sky	750	no
Besançon	19.2	suburban sky	770	no
Saint-Denis (Réunion)	19.3	suburban sky	800	no
Caen	19.3	suburban sky	820	no
Brest	19.3	suburban sky	820	no
Biarritz	19.5	suburban sky	940	no
La Rochelle	19.9	suburban sky	1,280	no
Papeete	20.0	suburban sky	1,370	no
Chamonix-Mont-Blanc	20.5	rural/suburban transition	2,080	no
Queenstown	20.7	rural/suburban transition	2,290	no
Zermatt	21.5	rural sky	2,520	yes

Method: artificial sky brightness estimated from NASA night imagery (VIIRS Black Marble), with a propagation law calibrated on the World Atlas of Artificial Night Sky Brightness (Falchi et al. 2016): ±0.4 mag/arcsec². Stars: Hipparcos catalogue down to magnitude 6; naked-eye limit after Garstang. Planets: astronomy-engine. Meteor showers: International Meteor Organization.