At around 11 a.m. local time on Thursday, the Turkish Navy's Cesme hydrographic vessel sailed from its base in Constantinople (Κωνσταντινούπολις, Turkish: İstanbul) and reportedly sailed into the Bosphorus.
The question now is whether the hydrographic ship will sail to the area between the islands of Lemnos-Agios Efstratios and Skyros where it has stated that it will illegally carry out work from today until March 2.
This question has occupied the Greek government for the last 24 hours, with the Ministries of Foreign Affairs and National Defense collecting and decoding all the information that will help them compose an image of Ankara's challenges.
What is certain is that Navtex 0122/21 issued on Monday by the coastal station of Smyrna (Σμύρνα, Turkish: İzmir) is illegal since the Turkish side has no authority to issue a NAVTEX to seafarers for hydrographic work in the area.
Despite the fact that the coordinates given by the hydroelectric station of Smyrna create a large area in the centre of the Aegean and in international waters, the exclusive responsibility for licensing research in this area belongs to Greek services.
With this in mind, the Ministry of Foreign Affairs delivered a denouncement statement to the Turkish Embassy in Athens and the Turkish Ministry of Foreign Affairs in Ankara.
The Erdoğan regime said Cesme will proceed with research work for a period of 13 days, from today until midnight on March 2.
As shown on the map, the area of research that Ankara warned that Cesme would move into is just seven miles from Lemnos and Agios Efstratios and about 10 miles east of Skyros.
With this method, Ankara implicitly reiterates that it does not recognize Greece's right to a 12-nautical-mile coastal zone around the islands, as provided for in the Convention on the Law of the Sea.
The cunning Turkish movement with Cesme in the area where they have stated that investigations will be carried out, intersects at the 25th meridian.
According to Ankara should be the limit for dividing the Aegean into two search and rescue zones.
Ankara is trying to claim the area east of the 25th meridian as part of its Search and Rescue Mission operations in the middle of the Aegean.
The 25th meridian intersects Agios Efstratios.
The area where the Turks have declared the Cesme will move for research is carefully designed to include an area - in international waters - east and west of the 25th meridian.
The Cesme research ship belongs to the Turkish Navy and is an old ship, designed for research operations.
It enlisted in the US Navy in 1965 and in 1999 was assigned to Turkey.
It has a length of 87 meters, can develop a speed of 15 knots and has a crew of 37 people.
Makis Pollatos is a correspondent for Proto Thema.