What does it mean when you say things like "The Moon passes 4° south of Mars"?
KAPIL DHAIMADE, MUMBAI, INDIA
Degrees (°) are the simplest way to measure angles. A full circle encompasses 360°, so 4° equals 1/90 of a circle. Scientists further divide angles into arcminutes ('), where 60'= 1°, and arcseconds ("), where 60"=1'. An arcsecond represents a tiny angle — it's the size a U.S. penny would appear at a distance of 2.4 miles (3.9 kilometers).