Snow gun for the production of artificial snow, of the type comprising: - at least one inlet mouth suited to be connected to a system for the supply of a liquid substance to be processed; - at least one outlet mouth for said artificial snow; - an evaporation chamber in which said liquid substance is introduced through said inlet mouth, said evaporation chamber being configured in such a way as to carry out a process of evaporation of a portion of said liquid substance in its triple point and substantially in vacuum conditions, obtaining steam and the removal of heat from the remaining non-evaporated mixture of said liquid substance constituted by a portion in the liquid state and a portion in the crystallization phase; - a condensation chamber communicating with said evaporation chamber through the interposition of compression means configured in such a way as to draw said steam from said evaporation chamber and substantially maintain a vacuum condition inside it, said condensation chamber being configured in such a way that it condensates said steam compressed by said compression means into a condensed liquid substance (Sc); - vacuum generating means connected to said condensation chamber and configured in such a way that they generate and successively maintain said evaporation chamber and said condensation chamber in vacuum conditions; - a crystallization tank connected to said evaporation chamber through a first duct and suction means for the transfer of said remaining non-evaporated mixture into said crystallization tank, said crystallization tank being configured in such a way as to implement a growth process of said portion in the crystallization phase so as to obtain said artificial snow; characterized in that said compression means comprise a thermocompressor communicating with said evaporation chamber through a first inlet and with a steam generator through a second inlet, said steam generator being configured so that it produces a high-pressure steam flow (Va) suited to compress said steam at the level of said first inlet so as to remove it from said evaporation chamber and to convey it towards said condensation chamber through an outlet of said thermocompressor, said condensation chamber being in communication with said steam generator in such a way that said condensed liquid substance (Sc) is vaporized and re-introduced in the cycle in the form of said high-pressure steam (Va). - at least one inlet mouth suited to be connected to a system for the supply of a liquid substance to be processed; - at least one outlet mouth for said artificial snow; - an evaporation chamber in which said liquid substance is introduced through said inlet mouth, said evaporation chamber being configured in such a way as to carry out a process of evaporation of a portion of said liquid substance in its triple point and substantially in vacuum conditions, obtaining steam and the removal of heat from the remaining non-evaporated mixture of said liquid substance constituted by a portion in the liquid state and a portion in the crystallization phase; - a condensation chamber communicating with said evaporation chamber through the interposition of compression means configured in such a way as to draw said steam from said evaporation chamber and substantially maintain a vacuum condition inside it, said condensation chamber being configured in such a way that it condensates said steam compressed by said compression means into a condensed liquid substance (Sc); - vacuum generating means connected to said condensation chamber and configured in such a way that they generate and successively maintain said evaporation chamber and said condensation chamber in vacuum conditions; - a crystallization tank connected to said evaporation chamber through a first duct and suction means for the transfer of said remaining non-evaporated mixture into said crystallization tank, said crystallization tank being configured in such a way as to implement a growth process of said portion in the crystallization phase so as to obtain said artificial snow;