Editing Solar radius (section)

{{short description|Unit of measurement}}
{| class="wikitable floatright"
|+ Conversion of nominal solar radius
! 1 {{solar radius}} =
! Units
|-
| {{val|6.95700|e=8}} || [[metre]]s
|-
| 695,700 || [[kilometre]]s
|- 
| 0.00465047 || [[astronomical unit]]
|-
| 432,288 || [[mile]]s
|-
| {{val|7.35355|e=-8}} || [[light-year]]
|-
| {{val|2.25461|e=-8}} || [[parsec]]
|-
| 2.32061 || [[light-second]]s
|}

'''Solar radius''' is a unit of [[distance]] used to express the size of objects in [[astronomy]] relative to the [[Sun]]. The solar [[radius]] is usually defined as the radius to the layer in the [[Sun]]'s [[photosphere]] where the [[Optical_depth_(astrophysics)|optical depth]] equals 2/3:<ref name='Hab2008' />

<math display="block">1\,R_{\odot} = 6.957\times 10^8 \hbox{ m} </math>

{{convert|695,700|km|mi|abbr=off}} is approximately 10 times [[Jupiter radius|the average radius]] of [[Jupiter]], 109 times [[Earth radius|the radius]] of the [[Earth]], and 1/215 of an [[astronomical unit]], the approximate distance between Earth and the Sun. The solar radius to either pole and that to the equator differ slightly due to the Sun's [[stellar rotation|rotation]], which induces an [[flattening|oblateness]] in the order of 10 parts per million.<ref>{{Cite web |url=https://science.nasa.gov/science-news/science-at-nasa/2008/02oct_oblatesun/ |title=NASA RHESSI oblateness measurements 2012 |access-date=2017-07-12 |archive-date=2018-09-17 |archive-url=https://web.archive.org/web/20180917185431/https://science.nasa.gov/science-news/science-at-nasa/2008/02oct_oblatesun/ |url-status=dead }}</ref>