ASTRI (Astrophysics with Italian Replicating Technology Mirrors) started as a MIUR flag project approved in 2010 to support the development of technologies within the CTA project (Cherenkov Telescope Array).

CTA is an international program aimed at building a ground astrophysical observatory for gamma rays, involving more than 200 institutions belonging to 31 European and extra-European countries. The funding of the ASTRI project allows the INAF community to be a leading player in the CTA.

The first result of the ASTRI project was the construction, almost entirely made by Italian companies, of a prototype telescope now installed at Serra La Nave (INAF-Catania).

The ASTRI prototype is the first telescope for Cherenkov astronomy to have adopted the Schwarzschild-Couder optical configuration that uses two mirrors, instead of just one as all the other Cherenkov telescopes currently in operation. The presence of the secondary mirror makes the telescope more compact and reduces the image size on the focal plane allowing the use of small, light and low-consumption detectors.

The ASTRI prototype telescope is essentially a technological demonstrator whose validation has however occurred through the observation of astrophysical gamma sources.

The next phase of the project, currently underway, sees INAF involved in the construction of a series of precursors (9 units defined as “pathfinder”) of telescopes of the SST class (Small Size Telescope) for the CTA observatory. These precursors, based on the optimization of the ASTRI prototype telescope, could be hosted and tested in the southern hemisphere chosen to host the observatory.