Monday, November 26, 2007

ASTRONOMY Q/A 7

1. Right ascension is prmarily used by the navigator for ? Plotting on star finders.

2. The GHA of the first point of Aries is 315° and the GHA of a planet is 150°. What is the right ascension of the planet ?
11 hours.

3. The angle that is measured westward from the first point of Aries to the hour circle of the body along the celestial equator is the ?
Sidereal hour angle.

4. The celestial coordinate of a star that is relatively constant in value is the ? Sidereal hour
angle.

5. The difference (measured in degrees) between the GHA of the body and the longi tude of the observer is the ?
Meridian angle.

6. The arc of a great circle which passes through the body and celestial poles is part of the ? Hour circle.

7. The ecliptic is ?
The path the Sun appears to take among the stars.

8. The navigator is concerned with three systems of coordinates. Which system is not of major concern ?
Ecliptic.

9. The equator is ?
The primary great circle of the Earth perpendicular to the axis.

10.The distance between any two meridians measured along a parallel of latitude ? Decreases with increased latitude.

11.The distance between any two meridians measured along a parallel of latitude and expressed in miles is the ?
Departure.

12.The angle at the pole measured through 180° from the prime meridian to the meridian of a point is known as ?
Longitude.

13. A plane perpendicular to the polar axis will never form what line on the Earth's surface ?
Meridian.

14. A plane that cuts the Earth's surface and passes through the poles will always form ? A
meridian.

15. A plane that cuts the Earth's surface at any angle and passes through the center will always form ?
A great circle.

16. A line on the Earth parallel to the equator is a ? Small circle.

17. A parallel of latitude other than the equator is a ? Small circle.

18. The angle measured at the observer's meridian from the elevated pole, clockwise or counterclockwise up to 180°, to the vertical circle of the body is the ? Azimuth angle.

19. The azimuth angle of a sun sight is always measured from the ?
Elevated pole.

20. An azimuth angle for a body is measured from the ?
Observer's meridian.