The country’s only Geomagnetic Observatory is located in Penteli and operates under the EAGME. It was founded in 1957 through the efforts of the former Institute of Geology and Subsurface Research (IGEY) and serves as the successor to the Magnetic Observatory of the State Geodetic and Geophysical Committee at Tatoi Military Airport, which was destroyed by bombing in 1941.
At the Penteli Geomagnetic Observatory (G.S.P.), absolute measurements are carried out for the declination, inclination, horizontal, and vertical components of the geomagnetic field across Greece. The geomagnetic field serves as the planet’s “shield” against the sun’s ultraviolet radiation and is continuously changing in intensity and direction. The recorded data are also used to detect and characterize rapid geomagnetic phenomena, such as magnetic storms and solar flares.
Inside a specially constructed building—free from magnetic interference (e.g., high-voltage pylons, vehicles, etc.)—and within a 10-meter tunnel excavated in marble with ideal thermal insulation, two triaxial magnetometers are installed to continuously record the three components of the geomagnetic field, along with one magnetometer measuring the total field intensity. All instruments are connected to a digital control and recording system that ensures the full reliability of the measurements. Additionally, the surrounding area includes special calibration platforms for instruments measuring radioactivity.
In recent years, the Penteli Geomagnetic Observatory has been upgraded with telemetry for remote data transmission. On November 17, 2010, the international network of magnetic observatories, INTERMAGNET, officially included the G.S.P. among its collaborating members.
The Observatory’s activities are diverse and wide-ranging, and it maintains strong collaborations with both public and private institutions:
- Supports international geophysical studies by providing direct online access to geomagnetic data (www.intermagnet.org).
- Provides geomagnetic data to international institutes and organizations.
- Collaborates closely with the Hellenic Military Geographical Service, which issues magnetic maps of Greece every five years.
- Supplies selected data to research groups, such as the psychiatric committee of Aeginiteio Hospital, for studies on the effects of geomagnetic variations on melatonin secretion—a key hormone influencing human psychophysical behavior.
- Conducts exclusive magnetic surveys at airports to identify or verify “clean” compass calibration areas for aircraft and military helicopters (e.g., Kotroni Marathon, Hellenic Navy helicopters).
- Uses its data to explore possible correlations between geomagnetic variations, earthquakes, and rainfall levels.
- Applies daily variation corrections of the geomagnetic field during field-based geophysical magnetic surveys.
- Collaborated with the Aristotle University of Thessaloniki and the University of Tirana to develop Albania’s geomagnetic network as part of the “Albanian Geodetic Reference System” program.
- Provides data to university students for the preparation of their thesis projects.
The Penteli Geomagnetic Observatory operates under the supervision of the Applied Geophysics Department of EAGME, with scientific coordinators Mr. G. Filippopoulos, Mr. P. Tsailas, and Mr. P. Kapiris.