Quantum redactiones paginae "Annus luce mensus" differant

'''Annus luce mensus'''<ref>[http://eweb.furman.edu/~dmorgan/lexicon/silva.htm Lexicon Morgan]; [http://books.google.fi/books?id=0PXHgsvKqkkC&pg=PA79&lpg=PA79&dq=%22annus+luce+mensus%22&source=bl&ots=phETBFMJUL&sig=Fr4J3aswEaX9OaqbwvCBiKROr40&hl=fi&ei=Ev-qTrb9J8P34QTzjYXdDg&sa=X&oi=book_result&ct=result&resnum=1&ved=0CBsQ6AEwAA#v=onepage&q&f=false José Juan Del Col, ''Diccionario auxiliar: español-latino para el uso moderno del Latín.'']; Tuomo Pekkanen & Reijo Pitkäranta, ''Lexicon hodiernae Latinitatis Finno-Latino-Finnicum'' (Helsinki: SKS 2005) s.v. ''Valovuosi''.</ref><ref>[[Ebbe Vilborg]]. ''Norstedts svensk-latinska ordbok''. Editio secunda anni 2009.</ref> sive '''spatium lucis annuae'''<ref>{{fontes desiderati}}.</ref> (abbreviatio internationalis '''ly''' de[[Lingua AnglicoAnglica|Anglicae]] ''light year'', "annus luminaris") est illud spatium quod lux per unum [[annus|annum]] in spatio vacuo pervolare potest. Unus annus luce mensus aequat fere 9 460 500 000 000 [[chiliometrum|km]]. Longitudo exacta dependet a definitione anni (sive annus tropicalis sive annus Iulianus sive annus sideralis significatur). [[Unio Astronomica Internationalis]] annum Iulianum praefert. Itaque 1 ly aequat 9 460 730 472 580 800 [[metrum|m]]. Unum spatium lucis annuae aequat 63 240 [[unitas astronomica|ua]] (unitatum astronomicarum) vel 0,3066 pc (parsec).