Magnetic Observatories

 PERMANENT MAGNETIC OBSERVATORIES

 REPUBLICA ARGENTINA

   By  JULIO CESAR GIANIBELLI

 

 

INTRODUCTION.   The aim of Permanent Magnetic Observatories is to record absolute variations in some or all the elements of the Earth Magnetic Field in magnetic Decline, Magnetic Tilt, North, East, Vertical, Horizontal Components and Field Total Intensity.  Figure 1 shows the Permanent Magnetic Observatories Network and the location of those which correspond to Argentina:

 

  • Pilar (PIL, Lat: 31° 40' 03"S Long: 63° 52' 53"W.),
  • Las Acacias (LAS, Lat: 35º 00,5’S; Long:57º 41,65’W),
  • Trelew (TRW, Lat: 43º 16,1’S; Long: 65º 22,9’W) e
  • South Orcadas Islands (ORC: Lat: 60° 44′ 20″S; Long: 44° 44′ 17″O).

 

 

FIGURE 1

 Permanent Magnetic Observatories are made up of non magnetic check boxes, one for variations record and the other for absolute observations related to the definition of relative records baseline.

 MAGNETIC OBSERVATORY IN PILAR.  It is the oldest Observatory in Latin America: its records on paper started in1904. The system was changed in February 2010 to INDIGO system, with digital record every minute. Figure 2 shows the location of checkboxes and headquarters.

 

 FIGURE 2

 

 INDIGO  system is shown in Figures 3a, 3b, and 3c.  Figure 3d shows the Theodolite with a flux-gate probe to assess/ measure Magnetic Decline and Tilt.

      

FIGURE 3a                                                 FIGURE 3b

 

     

FIGURE 3c                                                 FIGURE 3d

 

 MAGNETIC OBSERVATORY IN LAS ACACIAS. This Observatory started working in 1961 with photographic record system which stopped in1987. A Total Intensity of Magnetic Field record started working in 1993 with a Proton Precession magnometer modified for digital record every 1 minute for longer intervals to calendar month. Figures 4a y 4 b show the check box where both this operating system and the system itself are seen/ kept.

 

 

FIGURE 4a                                                     FIGURE 4b

 

MAGNETIC OBSERVATORY IN TRELEW. It started operating in 1957 with magnetograms on photographic paper until 1993, when digital records started. Figure 5a shows an aerial view of checkboxes and offices.  Figures 5b, 5c, y 5d se present Flux-Gate sensors and magnetic  theodolite for definition of Magnetic Decline and Tilt.

 

 FIGURE 5a

 

   

FIGURE 5b                             FIGURE 5c                        FIGURE 5d

 MAGNETIC OBSERVATORY IN SOUTH ORKNEY ISLANDS . It started working on photographic paper records in1905 which were replaced in 2011 by a digital one, similar to that in Pilar.  Figure 6a shows checkboxes location of variometers and absolutes. Figures 6b and 6c show these in detail. 

 

FIGURE 6a

 

   

FIGURE 6b                                                  FIGURE 6c

 There is data about formation of  the permanent observatories described , in the World Centers of.