Earthshapes are a series of 12 hypothetical Earths as conceived by American airman Joseph Portney in 1968 during a flight to the North Pole onboard a US Air Force KC-135. As the North Pole was reached, Portney looked on the icy terrain below and asked himself, "What if the Earth were...?"

The hypothetical Earths, cylindrical, conic, donut-shaped, and so forth, were sketched and captioned by Portney and given to the Litton Guidance & Control Systems graphic arts group to create models. These models were then photographed and became the theme of a Litton publication entitled Pilots and Navigators Calendar for 1969. Each month was introduced with a different one of the 12 hypothetical Earths. The result was an international sensation, attracting awards and heavy fan mail.