Question 1443Navigation General

The correct answer is B) 270°. To check the longitude of your vessel, you should observe a celestial body on a bearing of 270°, which is due west. This is because the longitude of a vessel is determined by comparing the time at the vessel's location with the time at a known reference location, such as Greenwich, England. Observing a celestial body on a bearing of 270° allows you to accurately measure the time at your vessel's location, which can then be used to calculate the longitude. The other options are incorrect because they do not represent the optimal bearing for determining longitude. A) 209° is the course of the vessel, not the bearing for longitude observation. C) 299° and D) 000° are not the optimal bearings for this purpose.