Formulae. 1  Eclipsing binary: diameter = speed Ã time of eclipse. 2  Size from luminosity: star's radius/Sun's radius = (Sun's temperature/star's temperature)2 Sqrt[star's luminosity/Sun's luminosity].
MOA is a mathmatical concept that most firearm scopes incorporate. Minute of Angle (MOA) is critical to sighting in your scope. MOA mathematical concepts were used to develop the AccuScope scope sighting reference tool. The only MOA information needed to use AccuScope is your scope's MOA number.
Be aware of 2 things: 1. Ranging with a mil or MOA reticle is a VERY PERISHABLE SKILL: if you don't practice, often, you will not be good at it. 2. Most scope manufacturers only calibrate a few points on the scale, not the entire magnification scale. If you scope is correct at 10X, do not assume you can double it at 5X and be on.