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Hammer projection
From Wikipedia, the free encyclopedia
The Hammer projection is an equal-area map projection, described by Ernst Hammer in 1892. Directly inspired by the Aitoff projection, Hammer suggested the use of the equatorial form of the Lambert azimuthal equal-area projection instead of Aitoff's use of the azimuthal equidistant projection:
where 
and 
are the x and y components of the equatorial Lambert azimuthal equal-area projection. Substituting:
where 
is the longitude from the central meridian and 
is the latitude.[1]
Visually, the Aitoff and Hammer projections are very similar. The Hammer has seen more use because of its equal-area property. The Mollweide projection is another equal-area projection of similar aspect, though with straight parallels of latitude, unlike the Hammer's curved parallels.
- ^ Flattening the Earth: Two Thousand Years of Map Projections, John P. Snyder, 1993, pp.130-133, ISBN 0-226-76747-7.