<h2>MGS MAG magnetic field</h2>
<br/>
   MGS magnetic field is available in two coordinate systems:
    <ol>
     <li><b>MSO</b> (sun-state, ss)<br/>
    The ss coordinate system is defined using the instantaneous               
    Mars-Sun vector as the primary reference vector (x direction).            
    The X-axis lies along this vector and is taken to be positive             
    toward the Sun. The Mars velocity vector is the second vector             
    used to define the coordinate system. The negative of the velocity        
    vector is used as a secondary reference vector so that the                
    vector cross product of x and y yields a vector z parallel to             
    the northward (upward) normal of the orbit plane of Mars. This            
    system is sometimes called a Sun-State (SS) coordinate system             
    since its principal vectors are the Sun vector and the Mars               
    state vector.         
     <li><b>Areographic</b> (planetocentric, pc)<br/>
     The planetocentric coordinate system is body-fixed and rotates            
    with the body as it spins on its axis. The body rotation axis             
    is the primary vector used to define this coordinate system. Z            
    is taken to lie along the rotation axis and be positive in the            
    direction of angular momentum. The X-axis is defined to lie in            
    the equatorial plane of the body, perpendicular to Z, and in              
    the direction of the prime meridian as defined by the IAU. The            
    Y axis completes the right-handed set.
    </ol>