NavList:

It's also interesting on the other end. Finding stars in morning twilight should be relatively easy. You start early! But since you're almost continuously observing them, you can also track stars until the sky is really quite bright. Following Venus up to the time of sunrise and beyond is possible at almost any point in its orbit.

Chasing earliest visibility of stars is a good navigation lesson, too. Far too many students of navigation are misled by the name "nautical twilight" and also by the emphasis on calculating the time of this in some navigation licensing exams. They get the impression that they can only see the stars for navigation during this period. But most of the brightest star, including Sirius, Capella, Vega, and Arcturus especially (northern hemisphere bias, yes) are visible much earlier than the start of nautical twilight in the evening sky.

Frank Reed