Sky measurements: Degrees, arcminutes and arcseconds

[elleng]

How do you describe how far apart something is in the sky? The fact is, the handiest measuring stick for the sky’s dome is the one on the end of your arm. You can use the width of your pinky, fist and more to gauge the distance between sky objects. That comes in handy when you’re observing conjunctions between planets, or close planets and stars, or planets and stars and the moon, plus many other space objects. You’ll often find these objects described as being a certain number of degrees, arcminutes or arcseconds apart.

https://earthsky.org/astronomy-essentials/sky-measurements-degrees-arc-minutes-arc-seconds/?