Final answer:
Vessels operating at sunset and sunrise must have navigational devices such as navigational charts, sextants, and lighting equipment on board for safe navigation.
Step-by-step explanation:
Vessels operating at sunset and sunrise must have certain devices on board to ensure safe navigation. One important device is a navigational chart that provides information about the position of the noontime Sun for a specific date. Navigation tables exist to calculate the proper angle of the noontime Sun for any other date. Another device is a sextant, which is used to measure the angle between the Sun and the horizon. This information is then used to determine the vessel's latitude. Additionally, vessels should have proper lighting equipment, such as navigational lights, for visibility during nighttime operation.