Which time factors must be considered when determining the Evening Star?

To accurately determine the Evening Star, several critical time factors must be considered, including sunset, the end of civil twilight, and the end of nautical twilight.

Sunset marks the moment when the sun disappears below the horizon, initiating the transition into twilight periods. This is the starting point for observing celestial bodies, as it signals the sky becoming darker.

Following sunset, civil twilight occurs, lasting until the sun is approximately 6 degrees below the horizon. During civil twilight, enough natural light remains for most outdoor activities, but this period is essential for astronomical observations as the sky begins to darken.

The next phase is nautical twilight, which lasts until the sun is about 12 degrees below the horizon. This is particularly important for navigation at sea because during nautical twilight, the horizon is still visible at sea, and navigators can take observations of stars, including the Evening Star, which is often Venus.

Understanding these phases helps navigators determine the best moments to observe celestial objects, making all of these time factors relevant in finding the Evening Star accurately. Therefore, it is crucial to consider sunset and both twilight phases in the process.