from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A unit of angle; 1/60th of a degree.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a unit of angular distance equal to a 60th of a degree
Sorry, no etymologies found.
The scale of the Hubble/VLA/Chandra image is probably on the scale of arcminutes (1 arcminute = 60,000 milliarcseconds).
Groups and clusters of galaxies can be effectively found using their extended x-ray emission on sub-arcminute scales.
However, this does not take into account the optics of the system which degrade image quality somewhat giving a commonly accepted resolution of 1 arcminute/cycle.
So, if a normal human eye can discriminate two points separated by 1 arcminute/cycle at a distance of a foot, we should be able to discriminate two points 89 micrometers apart which would work out to about 287 pixels per inch.
See, I'm just biased towards interferometers; -) ** One arcsecond is 1/60th of an arcminute, and one arcminute is 1/60th of a degree.