Where am I? 19,20
As our school is not on the sea and even not close to it, I will have to apply an artificial horizon. This can be a non-transparent bowl of water, protected against the wind. The angle I will measure will be between the alighted sun reflecting in the water and the sun reflected in the index mirror (Figure 4). Thanks to this clever measurement, I will avoid the necessity of application of the DE and HC, because the sun is adjusted as a whole and the eye is just above the horizon. However, the corrected altitude (with applied IC) will have to be divided by 2 as we do not observe the real horizon directly. My sextant was made in 1917 and its precision is 0.1°. The measurements are taken in front of the newly open
Figure 4: The application of the artificial horizon.
Laboratory I present all of it on the following page:
19 “ Nautical Almanac,” [Online]. Available: http://www.nauticalalmanac.it/en/pd-eng-nautical- almanac/file/49-nautical-almanac-2015.html. [Accessed 16 April 2015]. 20 “Quadratic Least Square,” [Online]. Available: http://www.azdhs.gov/lab/documents/license/resources/calibration-training/12-quadratic-least-squares-regression- calib.pdf. [Accessed 22 April 2015].
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