2

The sunset glow of the evening sky

Moonlight passing through the clouds

The brightening of the night sky

Electric lights of cars, street lamps, factories & buildings

Lights from outdoor advertisements

Background light from faint unresolved stars and nebulae

Faint air glow in the upper atmosphere

Anthropogenic activities

Yes

No

Over-illuminated commercial areas, sport complexes & stadiums

Densely populated cities

Suburban streets and housing estates

Nocturnal animals are able to see better

Disruptions in biological rhythms

Increased difficulty in viewing celestial objects