VIII Work with your partner asking and answering the given questions to talk about the text.1 Do human navigators use sextants to measure the elevation angle of celestial bodies above the visible horizon? 2 When does the peak elevation angle occur? 3 When can latitude be calculated by simple arithmetic from a table of declination? 4 Were these fixes hand-calculated using logarithms, then plotted on charts by a navigator? 5Whenwere hand-held bubble-level sextants built to measure the elevation of celestial bodies from an aircraft without the need to see the horizon? 6 Where did the human navigator observe sun and stars through an astrodome? 7Was the accuracy of celestial fixes 5–50 miles in the air oron the ground? 8 Wheredoes Kayton review the history of celestial navigation? 9 When did the first automatic star trackers, build? 10 Do approximate position measurements by dead reckoning allow the telescope to point within a fraction of a degree of the desired star? 11What does an on-board computer store? 12 Does clever design of the optics and of stellar-inertial signal-processing filters achieveaccuracies better than 500 feet or 800 feet? 13 Where may future lower-cost systems mount the star tracker directly? IX Do the test.
1 When were the first automatic star trackers built? A) In 1930
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