Editing Ring Nebula (section)

== Notes ==
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<li>{{Note label|A|a|none}}Radius = distance × sin(angular size / 2) = {{val|2.3|+1.5|-0.7|u=kly}} * sin(230″ / 2) = {{val|1.3|+0.8|-0.4|u=ly}}</li>
<li>{{Note label|B|b|none}}8.8 apparent magnitude − 5 × (log<sub>10</sub>({{val|700|+450|-200|u=pc}} distance / 10 pc)) = {{val|-0.2|+0.7|-1.8}} absolute magnitude</li>
<li>{{Note label|C|c|none}}Specifically in the north of Lyra which makes it visible from everywhere above about the [[47th parallel south]]. However the Sun passes through Sagittarius far to the south (or technically the Earth orbits so as to make the Sun seem to do so) throughout December. This also makes the cluster mostly risen during day, not night, in the nearest months but will never impede pre-dawn and post-sunset views from the upper half of northerly latitudes.</li>
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