Assertion: star's position | /r/HasProperty | fixed by angular measurement
Facets:
value: at right angles to each other
type: MANNER
value: from two planes of reference
type: LOCATION
Source sentences:
text: The position of any point on the surface of a sphere may be fixed by angular measurement from two planes of reference at right angles to each other passing through the centre of the sphere; these measurements are called the spherical coordinates of that point.