ultramarin marine translations

ultramarin.online
	nautisch-sterrenkundige driehoek		sferische driehoek aan het hemelgewelf met de hoekpunten pool-zenit-ster. De zijden van het driehoek zijn gegeven door de poolafstand van het hemellichaam, door de zenitafstand en door de eclipticabreedte;
	nautisch-astronomisches Grunddreieck sphärisch-astronomisches Grunddreieck Poldreieck		sphärisches Dreieck an der Himmelskugel mit den Eckpunkten Pol-Zenit-Gestirn, dessen Seiten von der Poldistanz des Himmelskörpers, vom Zenitabstand, sowie vom Breitenkomplement des Betrachters gebildet werden.
	astronomical triangle navigational triangle celestial triangle triangle of position		a spherical triangle on the celestial sphere whose vertices are the pole, the zenith, and the observed celestial body. One side is the polar distance of the celestial body, another the zenith distance, and the third the co-latitude of the observer.
	triangle astronomique de position
	triángulo de posición triángulo de navegación
	triangolo di posizione triangolo di navigazione

	PN  Noordpool Nordpol North Pole Pôle Nord Polo norte Polo nord GP geografische positie Sternbildpunkt  substellar point position géographique posición geográfica posizione geografica EP gegiste positie gegißte Position estimated position position estimée posición estimada posizione stimata GC grootcirkel door GP en EP Großkreis durch GP und EP great circle through GP and EP grand cercle par GP et EP gran círculo por GP y EP cerchio massimo per GP e EP t lokale uurhoek Ortsstundenwinkel local hour angle (LHA) angle horaire locale ángulo horario local angolo orario locale δ declinatie Deklination declination déclinaison declinación declinazione φ breedte Breite latitude latitude latitud latitudine Z azimuthoek Azimutwinkel azimuth angle angle d'azimut ángulo acimutal angolo azimutale
	The navigational triangle is a spherical triangle formed on the earth's surface by the North Pole (PN = true North), the observer's estimated position (EP) and the geographical position of the celestial body (GP). These points are connected by great circles, two of which are meridians: PN—GP being the Greenwhich hour angle of the geographical position, PN—EP being the longitude for the estimated position. There are six angles associated with any spherical triangle. In the navigational triangle, three of these angles are known, leaving three unknown angles. We need to find two of them to determine the azimuth and the calculated altitude. - The calculated altitude is derived from the angle 90° - Alt. which is shown in the drawing. When this angle is zero for example, the celestial body will be directly overhead and the altitude of the celestial body will be 90° above the horizon. - Similarly, the azimuth angle shown is the obverse of the included angle in the triangle which is actually calculated. It is shown this way because the azimuth is defined as the bearing of the geographical position as measured clockwise from true North. If the GP and the EP were swapped over in this diagram, the azimuth would then be the included angle in the triangle. - Using the estimated position and the geographical position as inputs, sight reduction tables will give the calculated altitude and azimuth as outputs. However, it is fairly easy to derive the calculated altitude and azimuth on a calculator using the equations: Dec declination of the celestial body Lat. latitude of estimated position LHA local hour angle between the two positions   * Declinations and latitudes south of the equator are negative; The Azimuth derived using these formulae will always be an angle less than 90°, so a correction will need to made depending on the azimuth quadrant in which the observed celestial body is located. If the observed body is in the West and South, add 180° to obtain the correct Azimuth. If the observed body is in the West and North, subtract the derived azimuth from 360° to obtain the correct azimuth. If the observed body is in the East and South, subtract the derived azimuth from 180° to obtain the correct Azimuth. If the observed body is in the East and North, the derived azimuth is correct.