MT-2221 - Celestial Navigation I

The expected outcome is that the student...	Supports STCW elements...
TOPIC - The Universe states course objectives, reviews learning material used and explains grading system describes the composition and dimensions of the solar system, explains astronomical distance in space describes the celestial sphere, relative, apparent and proper motion in space explains the magnitude ratio and relative brightness of the navigational stars and planets describes planetary configurations and names inferior and superior planets, explains the concept of the nodes explains the concept of direct and retrograde motion, describes the moon's orbit and its phases, libration, augmentation, the lunar and solar eclipse phenomena, states the approximate perigee and apogee distances describes horizontal and geocentric parallax describes the earth's elliptical orbit, and states approximate perihelion and aphelion distances and dates explains the eccentricity of the earth's orbit, time and the calendar describes the inclination of the earth's axis to the plane of the orbit and the stability of the axis (ignoring precession) and shows how it causes the seasons states the dates and describes the solstices and equinoxes explains the concept of the earth's axial rotation giving day and night explains the varying length of daylight through the year and the periods of the twilight's explains daylight and darkness conditions in various latitudes at the solstices and equinoxes describes the significance of the tropics of Cancer and Capricorn and of the Arctic and Antarctic Circles	21A6
TOPIC - Celestial equator system of coordinates defines the celestial sphere explains the apparent annual motion of the sun and the concept of the ecliptic defines "celestial poles": elevated and depressed defines "celestial meridians": upper and lower branch, prime meridian, latitude and co-latitude explains "celestial equator" and the "obliquity of the ecliptic" defines hour circle, diurnal circle, declination and polar distance explains the celestial equator as a fixed reference plane and the direction of the First Point of Aries as a reference direction (ignoring the effect of precession) defines "Greenwich Hour Angle (GHA)", "Local Hour Angle (LHA)", meridian angle and longitude and explains their relationships describes the concept of the earth's axial rotation causing change in the hour angle of bodies defines GHA of the Vernal Equinox, LHA of the Vernal Equinox defines "Sidereal Hour Angle (SHA)" and "Right Ascension (RA)" states the rate of change of GHA of the sun and Aries identifies the tabulation of SHA, GHA, and declination (and "d" and "v" corrections) in the Nautical Almanac for all celestial bodies determines the geographical position of a body for any given GMT	21A6 21A1.05
TOPIC - Horizon system of coordinates defines "rational, visible and sensible horizons", "zenith" and "nadir" defines "vertical circle" and "prime vertical circle" defines "elevated pole" and "depressed pole" proves that the altitude of the elevated pole above the celestial horizon is equal to the observer's latitude defines the observer's upper and lower celestial meridian identifies the apparent daily path of all bodies defines "true altitude", "azimuth", and "true zenith distance" explains the relationship between true azimuth, and azimuth angle recognizes rising and setting points and defines amplitude explains the meaning of the term circumpolar and describes the conditions necessary for a body to be circumpolar describes the condition necessary for a body to cross the prime vertical	21A6
TOPIC - Earth system of coordinates defines equator, poles, meridians, prime meridian, parallels, latitude, co-latitude, longitude identifies the equivalent of the coordinates in the horizon and celestial equator system of coordinates	21A1.05
TOPIC - Ecliptic system of coordinates defines the ecliptic, ecliptic poles, circles of latitude, circles of latitude through Aires, parallels of latitude, celestial altitude, celestial co-latitude, celestial longitude	21A6
TOPIC - Navigational triangle describes the vertices of the navigational triangle, "elevated pole", "zenith", "celestial body" describes the angles; "meridian (or LHA)", "azimuth" and "parallactic" which make up the inside of the navigational triangle and their relationship to the H.O. Pub. 229, Sight Reduction Tables for Marine Navigation shows the sides of the navigational triangle; "co-latitude", "polar distance", "zenith distance" and their compliments, "latitude", "declination" and "altitude" and their relationship to the H.O. Pub. 229, Sight Reduction Tables for Marine Navigation	21A1.01 21A1.05
TOPIC - Sextant and altitude corrections gives general definition and description of the marine sextant describes the optical principles of sextant operation describes and shows the parts of the marine sextant discusses the non-adjustable and adjustable errors in the marine sextant demonstrates how to read a sextant shows how to determine the error of perpendicularity, side error and index error shows how to correct a sextant into which has been introduced one or more of error of perpendicularity, side error or index error demonstrates how to determine the index error of the sextant by the horizon describes how to find the index error of the sextant by the sun defines "sextant altitude (Hs)" applies index error defines "dip", "refraction", "semi-diameter" and "parallax", and explains their causes, applies the corrections for these items and explains the factors determining their magnitude illustrates the effect of terrestrial refraction on the dip and distance of the sea horizon describes the purpose of altitude correction uses the altitude correction tables in the Nautical Almanac, including reference to critical tables, interpolation tables and low-altitude correction tables defines "apparent altitude (Ha)" and "observed altitude (Ho)" calculates celestial observations for the observed altitude (Ho) of the sun, stars and planets obtains the true zenith distance from the true altitude of the body uses the sextant for taking vertical and horizontal angles	21A1.01 21A1.05
TOPIC - Time and equation of time defines the apparent solar day and states the relationship between LHA (sun) and LAT defines the sidereal day and states that it is a fixed time interval explains the reasons for the sun's irregular rate of change of SHA and hence the necessity to adopt the astronomical mean sun for time keeping purposes defines the equation of time (Eq-t) and its components determines the Eq-t from the Almanac and its sign of application defines GMT, UTC, LMT and longitude defines the use of Lunar Time, the Lunar day and month defines zone times, standard meridian and daylight savings times explains how to alter the ship's time during a passage with change in longitude demonstrates the use of time signals discusses marine chronometers calculates the error of a chronometer or watch calculates chronometer rate shows which reference publications are refereed to obtain information about time signal broadcasts demonstrates the basic equivalency between arc and time and corresponding tables in the Nautical Almanac shows the use of the Time Diagram to assist the navigator in visualizing time relationships assesses practical problems of arc/time conversions, mean time, zone time, apparent time, equation of time, sidereal time, hour angles of the vernal equinox and sidereal hour angles of stars	21A2.02 21A1.09
TOPIC - Nautical Almanac describes the information contained in general in the Nautical Almanac (NA) and in detail in the daily pages uses the tables of corrections and incremental corrections in the Nautical Almanac finds the GHA of a body for any moment in time finds the geographic position of a body through the calculation of hour angle and declination for any moment in time finds the LHA of a body, given the date, GMT and longitude of the observer explains the importance of the First Point of Aries finds the LHA of Aries, given the date, GMT and longitude of the observer explains what is meant by the sidereal hour angle of a star and obtains it from the Nautical Almanac derives the LHA of a star from the LHA of Aries and the SHA of the star uses the information in the Nautical Almanac to obtain the LMT of the meridian passage of a body to the nearest minute and interpolates for the observer's longitude when necessary discusses the miscellaneous calendar and planning data and auxiliary tables demonstrates the use of the Nautical Almanac in computing the time of Civil and Nautical Twilight's and Sunrise and Sunset calculates the LAT and LMT of the theoretical and visible rising and setting of the sun calculates the zone time (ZT) of sunrise, sunset, civil, nautical and astronomical twilight	21A1.05 21A2.02
TOPIC - Development of a line of position from the circle of equal altitude combines the equinoctial and horizon system of co-ordinates to determine the center and radius of a position circle and its direction in the vicinity of a selected position defines the "geographic position (GP)" of a celestial body shows the GP is the center of the circle of equal altitude explains what coordinates locate the GP on the surface of the earth proves the radius of the circle of equal altitude equals the zenith distance of the body shows the intersections of two circles of equal altitudes results in two intersections one representing the navigator's position or "fix" beneath the zenith shows the solution of high altitude sights using full circles of equal altitude shows due to the usually large radius of the circle, a short segment of arc can, for all practical purposes, be represented as a straight line determines the true azimuth of the body and explains how direction is determined from a point on the circumference of the circle to the center of the circle explains the comparison of "observed altitude (Ho)" to "calculated altitude (Hc)" determines the altitude intercept from the calculated circle of equal altitude to the actual circle of equal altitude finds the position of the observer at the time of the final observation, given two or more position lines with the courses and distances run between the observations	21A1.09
TOPIC - Solution of the "Navigational Triangle" by Sight Reduction Tables for Marine Navigation (H.O. Pub. No. 229) defines the entering arguments of LHA, assumed latitude and declination in whole degrees demonstrates the use of the tables to extract calculated altitude (Hc), altitude difference (d) and azimuth angle (Z) shows how to enter interpolation tables for the declination increment and altitude difference to correct to true computed altitude shows how to enter interpolation tables for exact "azimuth angle (Z)" shows how to convert interpolated azimuth angle (Z) to "true azimuth (Zn)" explains resultant "altitude intercept (a)" and "true azimuth (Zn)" demonstrates the solution of the navigational triangle by use of the calculator and spherical trigonometry demonstrates the use of fully interactive, integrated celestial navigation software programs commonly used aboard ships today demonstrates sight reduction, fix computation, true azimuth computation, star identification calculates a circle of equal altitude (high altitude sight) of the sun, stars and planets	21A1.01 21A1.05
TOPIC - Position plotting shows the calculation and plotting of a line of position for the sun, a star and a planet shows the calculation and plotting of a running fix for the sun, stars and planets calculates the 1200 running fix position	21A1.01 21A2.02
TOPIC - Latitude by meridian altitude makes use the meridian diagram to show the elevated pole, zenith and declination of a body lie along the same meridian and the navigational triangle flattening out to a line shows the declination of a body is numerically equal to the latitude of its "Geographic Position (GP)" shows the "zenith distance" of a body is equivalent to the distance on earth between the GP and the position of the observer applies the true zenith distance of a body when it is on the observer's meridian to the declination of the body, to obtain the observer's latitude shows how to apply these correctly when the declination and latitude have the same name and when of different name states the relationship between the altitude of the elevated pole and the latitude of the observer explains what is meant by a circumpolar star, and the terms upper and lower transit finds the value of the polar distance of the body, using its declination applies the polar distance to the true altitude of a body at lower transit to find the altitude of the elevated pole and the latitude states the direction of the position line through the observer when taking a meridian altitude assesses practical problems of calculating the time and latitude by meridian transit at upper and lower transit for the sun, stars and planets	21A1.01
TOPIC - Pole Star (Polaris) observations explains the movement of Polaris with change of latitude identifies Polaris describes the relationship between the altitude of Polaris and the observer's latitude deduces from that the altitude of Polaris with a few minor corrections equals the latitude of the observer obtains the corrections, -1°+ao+a1+a2, from Pole Star tables in the "Nautical Almanac" and applies them to the altitude of Polaris to find the latitude of the observer explains the importance of a line of position in the form of latitude shows the true azimuth of Polaris may be extracted directly from the tables	21A1.01
TOPIC - Determining compass error - Azimuth and amplitude obtains the error of the magnetic compass or gyrocompass by comparing the compass bearing of the body with the true azimuth of the body obtained at the time of observation obtains the true azimuth of the sun, star or planet from tables interpolating for the tabular azimuth angle, using GMT of observation, information from the Nautical Almanac, LHA of the body and the observer's DR position obtains the true azimuth of the by calculation, using GMT of observation, information from the Nautical Almanac, LHA of the body and the observer's DR position compares true azimuth with observed azimuth to determine error in the compass obtains the magnetic variation for the observer's position, using isogonal lines or other information on the chart applies variation to the error of the magnetic compass to find the deviation for the direction of the ship's head explains an azimuth observation of a rising or setting celestial body (amplitude) can be measured easiest and most accurately explains how the navigator determines when the center of the body is on the celestial horizon explains the corrections to be applied to the when the body is observed on the visible horizon calculates the amplitude for the sun, star or planet when on the celestial and visible horizon explains the inter conversion of azimuth and amplitude explains the effect of latitude on the accuracy of amplitude observations calculates the LAT and LMT of the theoretical and visible rising and setting of the sun extracts information from the tabulation of the rising and setting of the sun in the Nautical Almanac shows the use of the azimuth circle on the gyro repeater and magnetic compass	21A1.09
TOPIC - Identification of celestial bodies explains the Nautical Almanac's list of navigational information on the 19 first magnitude stars and 38 second magnitude stars, plus Polaris explains the use of star charts explains the use of the planet diagram in the Nautical Almanac demonstrates the use of the Rude Star Finder demonstrates the use of the Sight Reduction Tables for Air Navigation (Pub. No. 249) as a star finder for seven selected stars explains the use of the Sight Reduction Tables for Marine Navigation (H.O. Pub. No. 229) for pre-computation of altitude and azimuth angle of selected stars shows the use of astronomy software programs for locating the 57 navigational stars (including Polaris), diagraming their constellations, showing the rising, setting, and transit of bodies through the sky and the position of the navigational planets	21A1.01 21A1.05