Professional astronomy toolkit. Calculate telescope magnification, angular resolution, limiting magnitude, and stellar distances. Essential tools for amateur and pro astronomers.
Divide the focal length of the telescope by the focal length of the eyepiece. For example, a 1200mm telescope with a 25mm eyepiece provides 48x magnification.
Dawes' Limit is a formula (116 / aperture in mm) used to estimate the maximum resolving power of a telescope for separating close double stars.
A light year is approximately 9,460,730,472,580 kilometers. It is the distance light travels in a vacuum in one Julian year (365.25 days).