Sun Day (May 3, 1978) was designated by United President Jimmy Carter specifically devoted to advocacy for solar power, following a joint resolution by Congress, H.J.Res. 715 becoming Pub.L. 95–253 It was modelled on the highly successful Earth Day of April 22, 1970. It was the idea of Denis Hayes, who also coordinated Earth Day in 1970.
The first Fiesta del Sol was held in 1972. It was devised by the Director of Tourism of the Province of San Juan, Guillermo Barrena Guzman. In 1993, by resolution of the Secretaria de Turismo de la Nacion, the festival it became a nationalbecoming the "National Day of the Sun.
Resolved by the Seriate and House of Representatives of the United States of America in Congress, assembled, That May 3, 1978, is proclaimed "Sun Day", and the President is authorized and requested to issue a proclamation calling upon the general public, industry, and labor of the United States to observe such day with appropriate activities and ceremonies, and to direct all appropriate Federal
agencies to cooperate with, and participate in, the celebration of "Sun
Approved March 27, 1978. (92 STAT. 186 PUBLIC LAW 95-253—MAR. 27, 1978 )