GCN Alert: Messaggio GCN inviato alle 2025-12-18 05:13:37:

{
    "alert_type": "RETRACTION",
    "time_created": "2025-12-18T04:13:37Z",
    "superevent_id": "MS251218d",
    "urls": {
        "gracedb": "https://gracedb.ligo.org/superevents/MS251218d/view/"
    },
    "event": null,
    "external_coinc": null
}