Nav 4 Reviewer Questions Flashcards
(34 cards)
A celestial coordinate system that uses the observer’s local horizon as the fundamental plane to define two angles
The horizon system of coordinates
During winter solstice, Antarctic Circle experience how many hours of darkness?
0hrs
Find the LHA of star if the Observer’s Longitude is 8O°E, GHA of Aries is 75°, SHA of star is 145°and GHA of star is 225°.
305°
Great circle passing thru the center of the earth on the celestial sphere which means midway between ZENITH and NADIR
Rational Horizon
How many are there inferior planets?
2
Is a celestial body is the true compass direction from the observer to the observed celestial body
Azimuth
Is a system of stars, planets, moons, and other objects, bound together by gravitational orbit?
Solar System
It circle where the sky appears to meet the Earth when you’re observing from a particular location.
Celestial Horizon
It is a great circle on the celestial sphere representing the sun’s apparent path during the year, so called because lunar and solar eclipses can occur only when the moon crosses it.
Ecliptic
It is a great circle on the celestial sphere the pole of which is the Observer’s zenith or the great circle every point on which is 90 from the observer’s zenith.
Rational Horizon
It is a point in the sky about which all the stars seen from the Southern Hemisphere.
South Celestial Pole
It is a point in the sky about which all the stars seen from the Northern Hemisphere.
North Celestial Pole
It is a point vertically above the observer or a line joining from the center of the Earth through the observer to the celestial sphere.
Zenith
It is a point vertically below him or a point vertically opposite of Zenith on the celestial sphere.
Nadir
It is a semi-great circle on the celestial sphere joining the celestial poles or projection of the earth’s meridians on the celestial sphere.
Celestial Meridian
It is a small circle on the celestial sphere whose plane is parallel to the plane of rational horizon and passes through the eye of the observer
Sensible Horizon
It is an angle at the celestial pole contained between the celestial meridian of the First point of Aries and that through the body, measured westward from Aries.
Sidereal Hour Angle
It is an hour angle contained between the celestial meridian of the First point of Aries and the celestial meridian passing through the body, measured eastward from Aries.
Right Ascension
It is an hour angle contained between the observer’s celestial meridian and the celestial meridian through that body, measured westward.
Local Hour Angle
It is an hour angle of the body measured from observer’s meridian to the meridian of the body in easterly or westerly direction from 0° to 180°
Meridian Angle
It is an imaginary sphere surrounding the Earth.
Celestial Sphere
It is the angle at the celestial poles contained between the celestial meridian of Greenwich and celestial meridian passing through the body, measured westward from celestial meridian of Greenwich.
Greenwich Hour Angle
It is the arc of vertical circle passing through the body contained between the rational horizon and the center of the body.
True Altitude
It is the art of science of navigating by stars, sun, moon and planets, and is one of the oldest of human arts.
Celestial Navigation
