MAGDAS Project


Kiyohumi YUMOTO

Space Environment Research Center (SERC)

Kyushu University, Japan


November 2005




This document briefly outlines the forwarding-looking plans of this research center, Space Environment Research Center (SERC).  SERC seeks partners in developing nations to expand our global monitoring of the earth's magnetic field.  This document mentions the nations where our instrument (called MAGDAS) has already been successfully deployed.  Until now, deployment largely has occurred at points south and north of Japan, not east and west of Japan.


In the new year (i.e., Year 2006) and beyond, SERC would like to deploy its magnetometer (MAGDAS) at points near the geomagnetic equator, circumnavigating the globe.  The new points we are seeking are located at:

* Peru

* Brazil (near EUS point)

* Cote-D'ivoire

* Nigeria

* Ethiopia

* India

* Thailand (Phuket)

* The Philippines

* Yap Island  (part of the Federated States of Micronesia)

* Ponape

* Christmas Island

Additionally, we are seeking some new low-latitude points:

* Mexico

* Trinidad

* Brazil (Santa Maria)

* South Africa

* Italy

* Georgia (near Russia)


Our needs:

As mentioned above, SERC seeks partners in developing nations to carry out our sun-space-earth research using state-of-the-art technology.   (Our MAGDAS, described in more detail below, represents state-of-the-art technology.  It can be readily deployed in inhospitable locations, and send its data to SERC via the Internet in a near real-time manner.  In this respect, MAGDAS is unique.  It was designed from accumulated know-how from vast field experience around the world over many years.)


Partners must provide the following:

-         One IP (Internet Protocol) connection.  The load is small (80kbs).

-         A location away from electromagnetic noise sources (such as gasoline and electric motors of all kinds).  Vehicular traffic should be more than 200m away.

-         A small amount of maintenance (average would be about one hour per week).

-         Electricity (60W or so).

-         Security.  Theft of any component of MAGDAS is not desirable.

-         Finally, a ten-year commitment as a partner.


In return, the overseas partner will learn a great deal more about the international scientific community, and how it operates, how it plans, how it grows, how it exploits new technology (such as the Internet), how it educates the next generation of researchers, how it helps mankind, and how it secures funding from organizations that have funds.


Below is more information on our research effort.


(1) The instrument and network (collectively called MAGDAS):

   The Circum-pan Pacific Magnetometer Network (CPMN) was constructed by Kyushu University in collaboration with about 30 international organizations along the 210°magnetic meridian and magnetic equator during the international Solar Terrestrial Energy Program (STEP) period (1990-1997) as shown in Figure 1.     For space weather research and applications, the Kyushu University group is now deploying a new real-time MAGDAS (MAGnetic Data Acquisition System) in the CPMN region, and the FM-CW radar network along the 210°magnetic meridian.  Fifty new fluxgate-type magnetometers (shown in Figure 2) and their data acquisition systems send data from overseas sites to Fukuoka, Japan.  Before deployment, each instrument is rigorously tested at the Space Environment research Center (SERC), Kyushu University. 

    The new magnetometer system consists of a 3-axial ring-core sensors, fluxgate-type magnetometer, data logging/transferring unit, and power supply. Magnetic field digital data (H+δH, D+δD, Z+δZ, F+δF) are obtained at the sampling rate of 1/16 seconds, and then the averaged data are transferred from overseas stations to SERC in near real time.  The ambient magnetic field, expressed by horizontal (H), declination (D), and vertical (Z) components, are digitized by using the field-canceling coils for the dynamic range of ±64,000nT/16bit.  The total field (F+δF) is estimated from the H+δH, D+δD, and Z+δZ components.  The resolution of MAGDAS data are 0.061 nT/LSB and 0.031 nT/LSB for ±2,000 nT and ±1,000 nT range, respectively.  The estimated noise level of the MAGDAS magnetometers is 0.02 nTp-p.  The long-term inclinations (I) of the sensor axes are measured by two tiltmeters with 0.2 arc-sec resolution. The temperature (T) inside the sensor head is also measured.  GPS signals are received to adjust the standard time inside the data logger/transfer unit.  These data are logged into the Compact Flash Memory Card of 1 GB.  The total weight of the compact MAGDAS magnetometer system is less than 15 kg.  (all shown in Fig.3).  The instrument is entirely self-contained, except for power and IP needs.


 (2) People involved in the MAGDAS Project:

Project Leader: Prof. Dr. Kiyohumi Yumoto


Kyushu University

     Prof.  K. Yumoto , Dr. H. Kawano, Dr. A. Yoshikawa, Dr. M. Shinohara, Dr. T. Uozumi,

     Dr. Y. Obana, Dr. S. Abe,  and   Mr. G. Maeda

Tohoku Institute of Technology

     Dr. M. Seto, and Mr. Y. Kitamura



National Central University

      Prof. Tiger Liu, Mr. SW Chen



Coast and Geodetic Survey Department, National Mapping and Resource Information Authority

      Commodore RODOLFO M. AGATON, Dr. I. Nakagawa (JICA), Mr. Alex Algaba and

      Mr. Carter Luma-ang

Cagayan State University (northern Philippines)

       Prof. Joseph B. Acorda, Mr. Manuel P. Rosete, Dr. Diosdado B. Dimalanta, and

       Ms Maria Jackie Lou A. Liban

University of San Carlos (at Cebu)

       Dr. Roland Emerito S. Otadoy, Mr. Erwin Orosco

Magnetic Observatory (at Davao), Ateneo de Manila University Campus

       Fr. Badillo Victor L., Mr. Efren Morales



Space Science Application Center , LAPAN, Bandung

        Drs. Suratno, Mr Mamat Ruhimat

Badan Meteorolog dan Geofisika, MGA, Manado

        Drs. Subardio,

Potential Geophysics and Time Signals, Meteorological and Geophysical Agency of Indonesia

        Muhammad Husni



IPS Radio & Space Services

       Dr David Cole, Dr Phil Wilkinson, Dr Richard Marshall, Dr Dave Neudegg, Dr Mike Hyde

       Mr. George Goldstone

CSIRO, Wildlife & Ecology, TERC, Darwin

       Mr. Tony Hertog

Australian Antarctic Division (in charge of MacQuarie Island)

      Lloyd Symons, Dr. Ray Morris

La Trobe University, Victoria

      Prof. Peter L. Dyson



Institute of Cosmophysical Researches and Radio Wave Propagation (IKIR),  FEB RAS

       Prof. Boris Shevtsov

Institute of Cosmophysical Research and Aeronomics (IKFIA), Siberian Division RAS

       Dr. S.-I. Soloveyev, Dr. Dmitry Baishev

Pacific Ocean Institute, FEB RAS

      Dr. Valerian Nikiforov



Institute of Geophysics and Planetary Physics, UCLA

      Dr. Peter Chi

Minnesota State University

      Dr. Linda Winkler



 (3) Scientific objectives of the MAGDAS Project:

     The MAGDAS system is now being deployed in order to carry out space weather studies during the 2005-2008 time frame. We need to clarify the dynamics of geospace plasma changes during magnetic storms and auroral substorms, the electro-magnetic response of iono-magnetosphere to various solar wind changes, and the penetration and propagation mechanisms of DP2-ULF range disturbances from the solar wind region into the equatorial ionosphere.  The ordinary data can be used for studies of long-term variations, e.g. magnetic storm, auroral substorms, Sq, etc., while the induction-type will be useful for studies of ULF waves, transient and impulsive phenomena.  By using this new MAGDAS data, we can conduct real-time monitoring and modeling of (1) the global 3-dimensional current system and (2) the ambient plasma density for understanding the electromagnetic and plasma environment changes in the geospace. 

3.1. Global 3-D current system

   We will make the ionospheric equivalent current pattern every day using the MAGDAS data. At high latitudes the ionospheric currents are joined with field-aligned currents (FAC) from the solar wind region into the magnetosphere, and the electro-dynamics is dominated by the influences of solar wind-magnetosphere interaction processes.  The total current flow is on the order of 107 A.  On the other hand, the ionospheric current at middle and low latitudes is generated by the ionospheric wind dynamo, which produces global current vortices on the dayside ionosphere, i.e., counterclockwise in the northern hemisphere and clockwise in the southern hemisphere.  The total current flow in each vortex is order of 105 A.

   There are strong electric fields at high latitudes, on the order of several tens of millivolts per meter or more, depending on the magnetic activity.  At middle and low latitudes electric fields are considerably smaller, typically a few millivolts per meter during magnetically quiet periods.  During magnetic active periods the part of strong electric fields at high latitude can penetrate into middle and low latitudes, and then the global ionospheric current pattern must be re-organized strongly.  In reality the current and electric fields at all latitudes are coupled, although those at high, and middle and low latitudes have been often considered separately.  By using the MAGDAS ionospheric current pattern, the global electromagnetic coupling processes at all latitudes can be clarified during the CAWSES.

3.2. Ambient plasma density

   The field line resonance (FLR) oscillations in the Earth's magnetosphere are excited by external source waves, and are so-called as ultra low frequency (ULF) waves.  The amplitude of H-component magnetic variations observed at the ground stations reaches a maximum at the resonant point, and that its phase jumps by 180 degrees across the resonant point.  The eigen-frequency of FLR oscillations is dependent upon the ambient plasma density and the magnetic field intensity in the region of geospace threaded by the field line, and the length of the line of force. When we observe the eigen-frequency of FLR and assume models for the latitude profiles of the magnetic field and the plasma density (with the equatorial density as a free parameter), we can estimate the plasma mass density in the magnetosphere.  Therefore, the FLR oscillations are useful for monitoring temporal and spatial variations in the magnetospheric plasma density.  By using ground-based network observations, we can identify the FLR phenomena and measure the fundamental field-line eigen-frequency by applying the dual-station H-power ratio method and the cross-phase method, which have been established to identify the FLR properties.

   We have installed MAGDAS magnetometers at several pair stations along the 210°magnetic meridian, and we are currently observing magnetic FLR pulsations.  Each pair station is separated in latitude by ~100 km.  MAGDAS data will be analyzed by using two methods, i.e., the amplitude-ratio method and the cross-phase method.  As a result, we identify the FLR events and measure their eigen-frequencies, providing the plasma density varying with time. By using these results, we will discuss temporary variations of the ambient plasma density and the location of the plasmapause  during magnetic storms and auroral substorms.































Fig. 1. MAGDAS/CPMN (MAGnetic Data Acqusition System/Circum-pan Pacific Magnetometer Network) system of the SERC, Kyushu Univ.



























Fig. 2. The components of M AGDAS/CPMN magnetometer system for real-time data acquisition.

















Fig. 3.  MAGDAS magnetometer set





End of document.