Hover or tap underlined Spanish terms to see their translation and exam tip.
¿A qué se denomina "Ángulo Sidéreo (AS)"?How is “Sidereal Hour Angle (SHA / AS)” defined?
Show the answer
Correct answer: a) Arc of the celestial equator measured from Aries to the body’s hour circle from 0º to 360º in the retrograde/clockwise sense (viewed from Pn).
Why it is correct
Sidereal Hour Angle (SHA / AS) is the arc of the celestial equator measured from the First Point of Aries (♈) to the body’s hour circle from 0° to 360° westward—in the retrograde (clockwise when viewed from above the North Celestial Pole) sense.
Why the others are not
- b) That is the definition of the body’s declination (δ).
- c) That is the definition of polar distance or codeclination (90° ± δ).
- d) Measured from Aries in the direct/eastward sense (counterclockwise from Pn) is Right Ascension (RA).
How to work it out in the exam
- Sidereal Hour Angle (SHA): equatorial arc from Aries to the body, 0°–360° westward (clockwise viewed from Pn).
Where this question comes from
- Ministerio de Transportes (Madrid) · 2020 · Convocatoria de diciembre · CY Test 1 · question 8 Official paper · Official answer key
Pending instructor review. Machine translation, not reviewed.