milliarcsecond scale

A milliarcsecond is a very small unit of angular measurement used by astronomers to describe how finely they can see objects in the sky. One arcsecond is 1/3600 of a degree, and a milliarcsecond is 1/1000 of an arcsecond, making it extremely tiny. To put it into perspective, if you imagine the width of a human hair seen from about 1,000 kilometers away, that's roughly equivalent to a milliarcsecond in angular size. This precision allows astronomers to distinguish incredibly small differences in the position or structure of celestial objects, such as stars or galaxies.