The story of Perseus started in 1992, when two young amateur astronomers, Luigi Fontana and Marco Sala, wrote an innovative software for MS-DOS, called PPlus, that was distributed by ELItalia srl.

In those years, when very few planetarium softwares were available, the birth of a software in Italian, faster and more accurate of many of its competitors was a great achievement. PPlus had a feature that made it a great success: it was able to read the two CD-ROMs of the Guide Star Catalog, and so it was able to display almost 20 million objects.

Years later, in 1997, Luigi Fontana created a new software for the Windows 95, that was becoming the most used operating system. WinPPlus, as it was called, had many features from PPlus, while adding new ones, like the possibility of controlling the Meade LX200 telescopes that were becoming common.

Meanwhile, the developement of Perseus was started by Filippo Riccio, at first independently from the developement of WinPPlus. At this first stage the foundations of Perseus' realism were laid: the new representation for stars, that were not discs with varying diameter but single pixels with halos simulating the different brightness levels, and the RealDeep technology, which superimposed images to the sky to simulate nebulosity and galaxies.

The collaboration between Filippo Riccio and Luigi Fontana, who met at Circolo Astrofili di Milano, was born a little later, and in a short time it was possible to present officially and distribute Perseus at the Forlì astronomy fair of December 2001.

With respect to its predecessor, Perseus has many innovations, thanks also to the increased computing power of PCs. It is able to read the CDs of the USNO-A2.0 catalogue, with more than half a billion stars; it computes the positions of stars and planets with excellent accuracy while making real-time animations; and it has a print function that brings on paper some of the realism shown on the monitor.

From then, Perseus didn't stop evolving. Following the wishes of our users, that we cannot thank enough for all the advice and trust they gave us, new function were introduced, like the telescope control using the ASCOM platform and the creation of AVI movies.

From the end of 2007, Perseus is not distributed by ELItalia anymore, but directly by Filippo Riccio.