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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