Assertion: magnetic field's field line | /r/HasProperty | vertical
Facets:
value: at each pole
type: LOCATION
value: nearly
type: DEGREE
Source sentences:
text: At each pole, the magnetic field lines are nearly vertical.
text: If Earth's magnetic field were a perfect dipole then the field lines would be vertical at the Geomagnetic Poles, and they would coincide with the Magnetic Poles.