Transient localization web service based on open gravitational-wave data for the multi-messenger community.

We present here a web service https://virgo.pg.infn.it/maps integrated in the environment of the International Virtual Observatory Alliance (IVOA) and we sketch its implementation. The application has been developed in accordance with the FAIR (Findability, Accessibility, Interoperability, and Reusability) principles, allowing the efficient exchange of essential information between various partners in multi-messenger campaigns. The web tool provides an immediate and accurate visualisation of credible areas of a gravitational-wave sky localization issued by the the LIGO-Vrgo-KAGRA network (LVK). With this tool, any gravitational-wave source localisation, where  transient event is expected, can be intersected with the area available for a telescope providing the region of interest wherein a potential electromagnetic counterpart sits. Finally, we would like o point out the technological advantages of our service, from the point of view of future technical challenges, due to the anticipated exponential increase of gravitational transient detections as well as to the growth of a heterogeneous multi-messenger community.