Hover or tap underlined Spanish terms to see their translation and exam tip.
Sobre la esfera celeste, el punto cardinal Norte es la intersección de:On the celestial sphere, the North cardinal point is the intersection of:
Show the answer
Correct answer: c) The horizon and the observer’s upper meridian, if latitude is South.
Why it is correct
The observer’s upper meridian is the semicircle bounded by the celestial poles (Pn and Ps) passing through the zenith (Z). When the observer is in South latitude, Ps is the elevated pole (above the South horizon point on the lower meridian) and the upper meridian arc Ps–Z–Q–Pn intersects the horizon at the North cardinal point.
Why the others are not
- a) The horizon and celestial equator intersect at the East and West cardinal points.
- b) If latitude is North, the North cardinal point lies below the elevated North pole, on the lower meridian.
- d) The equator meets the meridian at Q and Q′, not at the horizon cardinal points.
How to work it out in the exam
- In South latitude: the upper meridian (Ps–Z–Pn) intersects the horizon at the North cardinal point.
Where this question comes from
- Junta de Andalucía · 2023 · 1ª convocatoria · CY Módulo de navegación · question 2 Official paper · Official answer key
Pending instructor review. Machine translation, not reviewed.