In a few months, the results of four years of intense effort by astronomers from the National Observatory of Athens, sponsored by ESA and led by Alceste Bonanos, will be unveiled. The Hubble Catalog of Variables (HCV) is the first full, homogeneous, catalogue of variable sources found in the Hubble Source Catalog (HSC), which is built out of publicly available images obtained with the WFPC2, ACS and WFC3 instruments. Hubble has been observing the sky for over 29 years and has visited some regions of the sky several times over its lifetime. This offers the opportunity to search for variable objects over a range of magnitudes that is difficult to reach with ground-based telescopes. https://www.spacetelescope.org/forscientists/announcements/sci19002/?lang