ASA 107 – Celestial Navigation Exam
Questions And Correct Answers (Verified
Answers) Plus Rationales 2025/2026 Q&A |
Instant Download Pdf
1. What is the angular distance of the Sun above the celestial horizon at local
noon called?
A. Azimuth
B. Zenith Distance
C. Altitude
D. Meridian Angle
Altitude is the angle between the celestial horizon and the Sun's position; at
local noon, it's at its maximum.
2. Which instrument is essential for measuring the angle between a celestial
body and the horizon?
A. Compass
B. Barometer
C. Sextant
D. Chronometer
The sextant is used to measure angular distances, crucial for celestial
navigation.
3. What correction must be applied to sextant altitude for the height of the
observer’s eye above sea level?
,A. Index Error
B. Dip
C. Refraction
D. Semi-Diameter
Dip corrects for the apparent lowering of the horizon due to the observer’s
height.
4. What is the purpose of a time sight?
A. Determine magnetic variation
B. Determine longitude
C. Determine latitude
D. Determine true north
A time sight uses the observed altitude of a celestial body to calculate longitude.
5. The Greenwich Hour Angle (GHA) is used to determine:
A. Magnetic deviation
B. Time of sunrise
C. Celestial body's position west of Greenwich
D. Latitude
GHA measures the angle westward from the Greenwich meridian to the hour
circle of a celestial body.
6. What is the line called that represents all positions from which a celestial
body is observed at the same altitude?
A. Rhumb Line
B. Prime Vertical
C. Circle of Equal Altitude
, D. Great Circle
The circle of equal altitude is also known as the position circle.
7. What publication provides tabulated values for celestial body positions?
A. Chart No. 1
B. Sailing Directions
C. Nautical Almanac
D. Coast Pilot
The Nautical Almanac provides GHA, declination, and other ephemeris data.
8. The observer’s geographical position on Earth directly under a celestial
body is called the:
A. Prime Meridian
B. Geographic Position (GP)
C. Celestial Equator
D. Subsolar Point
GP is the point on Earth directly beneath the celestial object.
9. What celestial body is most commonly used to determine true north?
A. The Sun
B. Jupiter
C. Polaris
D. Mars
Polaris, the North Star, remains nearly stationary over the North Pole.
10.Which angle increases toward the west up to 360 degrees in celestial
navigation?
Questions And Correct Answers (Verified
Answers) Plus Rationales 2025/2026 Q&A |
Instant Download Pdf
1. What is the angular distance of the Sun above the celestial horizon at local
noon called?
A. Azimuth
B. Zenith Distance
C. Altitude
D. Meridian Angle
Altitude is the angle between the celestial horizon and the Sun's position; at
local noon, it's at its maximum.
2. Which instrument is essential for measuring the angle between a celestial
body and the horizon?
A. Compass
B. Barometer
C. Sextant
D. Chronometer
The sextant is used to measure angular distances, crucial for celestial
navigation.
3. What correction must be applied to sextant altitude for the height of the
observer’s eye above sea level?
,A. Index Error
B. Dip
C. Refraction
D. Semi-Diameter
Dip corrects for the apparent lowering of the horizon due to the observer’s
height.
4. What is the purpose of a time sight?
A. Determine magnetic variation
B. Determine longitude
C. Determine latitude
D. Determine true north
A time sight uses the observed altitude of a celestial body to calculate longitude.
5. The Greenwich Hour Angle (GHA) is used to determine:
A. Magnetic deviation
B. Time of sunrise
C. Celestial body's position west of Greenwich
D. Latitude
GHA measures the angle westward from the Greenwich meridian to the hour
circle of a celestial body.
6. What is the line called that represents all positions from which a celestial
body is observed at the same altitude?
A. Rhumb Line
B. Prime Vertical
C. Circle of Equal Altitude
, D. Great Circle
The circle of equal altitude is also known as the position circle.
7. What publication provides tabulated values for celestial body positions?
A. Chart No. 1
B. Sailing Directions
C. Nautical Almanac
D. Coast Pilot
The Nautical Almanac provides GHA, declination, and other ephemeris data.
8. The observer’s geographical position on Earth directly under a celestial
body is called the:
A. Prime Meridian
B. Geographic Position (GP)
C. Celestial Equator
D. Subsolar Point
GP is the point on Earth directly beneath the celestial object.
9. What celestial body is most commonly used to determine true north?
A. The Sun
B. Jupiter
C. Polaris
D. Mars
Polaris, the North Star, remains nearly stationary over the North Pole.
10.Which angle increases toward the west up to 360 degrees in celestial
navigation?
