The Earth Orientation Center of which he is head belongs to the IERS which, until 2003, was the International Earth Rotation Service (it is now the Internationa

The Earth Orientation Center of which he is head belongs to the IERS which, until 2003, was the International Earth Rotation Service (it is now the International Earth Rotation and Reference Systems Service). So until 2003 there was, in fact, someone whose job title was "Head of International Earth Rotation Service".