Self-calibrating and autonomous magnetic observatory

A magnetic observatory (200) for measuring the local magnetic field vector ({right arrow over (F)}) comprising:

• a) a scalar magnetometer (MS) for obtaining the absolute measurement of the modulus of the local magnetic field vector (F);
• b) an angular magnetometer (MA) comprising:
• 1) a first holder (320) that is orientable about a first axis of rotation called the main axis of rotation (321) allowing a horizontal orientation of the first orientable holder (320) to be obtained, said first orientable holder (320) comprising:
• i. a main motor (322) for modifying the horizontal orientation of the first orientable holder (320) about the main axis (321);
• ii. a second holder (310) that is orientable about a second axis of rotation called the secondary axis of rotation (311) allowing a vertical orientation of the second orientable holder (310) to be obtained, orthogonal to the main axis (321), said second orientable holder (310) comprising:
• a secondary motor (312) for modifying the vertical orientation of the second orientable holder (310) about the secondary axis (311), and a magnetic sensor (323) for measuring the direction of the local magnetic field vector ({right arrow over (F)});
• 2) a means (340) for controlling the main and secondary motors (322 and 312);
• 3) a device (350) for angularly measuring and acquiring the horizontal and vertical orientations of the first and second orientable holders (320, 310);
• c) a magnetic variometer (MV) that records variations in three mathematically independent components of the local magnetic field vector ({right arrow over (F)});
• d) a clock (201);
• characterized in that,
• the first orientable holder (320) of the angular magnetometer (MA) furthermore comprises:
• an inclination sensor (313), mounted on the first orientable holder (320) or on the second orientable holder (310);
• the second orientable holder (310) of the angular magnetometer (MA) furthermore comprises:
• a north-seeking device (324);
• the observatory comprises a controller (202) configured to:
• a) automatically control the main motor 322 and secondary motor 312;
• b) manage the orientation of the:
• 1) inclination sensor (313) for measuring the direction of the vertical (V);
• 2) north-seeking device (324) for measuring the direction of geographic north (N);
• 3) magnetic sensor (323) for measuring the direction of the local magnetic field vector ({right arrow over (F)});
• c) acquire:
• 1) the angles of the direction of the local magnetic field vector ({right arrow over (F)}) with respect to geographic north (N) and to the vertical (V) depending on the horizontal and vertical orientations of the first and second orientable holders, which orientations are measured with the angularly measuring and acquiring device (350);
• 2) the three variations in the local magnetic field vector ({right arrow over (F)}) that are measured by the variometer (MV);
• 3) the values of the modulus of the local magnetic field vector (F) that are measured by the scalar magnetometer (MS);
• d) process the data acquired in step c) in order to automatically obtain the local magnetic field vector ({right arrow over (F)}) and the errors in the measurements associated with each instrument.