The scale bar (20 AU) represents 20 time the distance between the Earth and the sun. This star is about 41 parsecs away, so the angular size of that scale bar is about half an arcsec. (One degree is split into 60 arcminutes, one arcminute into 60 arcseconds. Just like a clock).

That angle is about the diameter of a US quarter coin seen from 11km (7mi) away.