The requested vessel with name ONEGA and MMSI:273370540 and IMO:0 is temporary not in our database.
Perhaps you mean one of the following ships:

Vessel name IMO MMSI In range Destination Last report
ONEGA 7825590 273445610 MURMANSK Feb 02, 2018 21:42 UTC
ONEGA1 N/A 273367730 Jul 18, 2017 14:52 UTC

Also, you may try to find the vessel in our comprehensive Vessels Database or track this ship on the map.