Artificial Night Sky Brightness
Explanation:
Where have all the dim stars gone?
From many places on the
Earth including major cities,
the
night sky
has been reduced from a
fascinating display of
hundreds of stars to a diffuse glow through
which only a handful of stars are visible.
The
above map indicates the relative amount of
light pollution that occurs
across the Earth.
The cause of the pollution is artificial light
reflecting reflect off of
molecules and
aerosols in the atmosphere.
Parts of the Eastern
United States and Western Europe
colored red have an artificial night sky glow
over nine times that of the natural sky.
In any area marked orange or red, the
central band
of our Milky Way Galaxy is no longer visible.
The
International Dark Sky Association suggests
common types of fixtures that provide
relatively little amounts of
light pollution.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.
