Geomagnetism

http://geomag.org/info/Declination/m...ation_2010.gif

The most underused observation is probably geomagnetism and specifically why it is not exactly North/South of the rotational Poles yet that is the dominant feature.

The North/South Poles turn parallel to the orbital plane each orbit and it is likely that the geomagnetic signatures arising from this orbit influence the position of the magnetic field at a present offset of over 11 degrees.

It is a remarkable omission insofar as the motion of the Sun through space in the solar system's galactic orbital motion would creation a planetary deflection thereby generating variable orbital speeds in line with the observations that planet's close to the Sun's Equator and magnetic field rotate faster.

The old notions as to the cause of why smaller objects orbit larger objects resurface again -

"The Sun and the Earth rotate on their own axes...The purpose of this
motion is to confer motion on the planets located around them;on the
six primary planets in the case of the Sun,and on the moon in the case
of the Earth.On the other hand the moon does not rotate on the axis of
its own body,as its spots prove " Kepler

Of course this era is dominated by people who somehow manage to contend with Kepler's final statement on the moon but thankfully they have vowed to keep their mouths shut.