The Mollweide projection is a map projection also called the elliptical projection or homolographic equal-area projection. The forward transformation is
 |  |  |
(1)
|
 |  |  |
(2)
|
where 
is given by
 |
(3)
|
Newton's method can then be used to compute 
iteratively from
 |
(4)
|
where
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(5)
|
(Snyder 1987, p. 251) or, better yet,
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(6)
|
can be used as a first guess.
The inverse formulas are
 |  | ![sin^(-1)[(2theta+sin(2theta))/pi]](/images/equations/MollweideProjection/Inline11.svg) |
(7)
|
 |  |  |
(8)
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where
 |
(9)
|
