However, I do know the angular size of the Sun (as seen from Earth) is about 0.53° -- yes, the distance from the Earth to the Sun does change, but I don't mind.

You may have come across the term 'angular spreading' in the Surfline forecasts—well here's what it means.

Earth is steadily spinning like a top, even if we can't see, touch, hear or feel it. So, what would happen if Earth were to abruptly stop rotating? If the spinning were to stop, the angular ...

By referring to charts that gave the star’s angular distance from the celestial equator, or declination, and determining the angle at the star, he could pinpoint his latitude.

The plan is to use angular size of the descent stage to get the distance from the rover in each frame of the video. But what is angular size, and what does it have to do with position?