Editing Surface brightness (section)

==Relationship to physical units==
The surface brightness in magnitude units is related to the surface brightness in physical units of [[solar luminosity]] per square [[parsec]] by{{Citation needed|date=April 2023}}
<math display="block">S(\mathrm{mag/arcsec^2}) = M_{\odot} + 21.572-2.5\log_{10} S (L_{\odot}/\mathrm{pc}^2),</math>
where <math>M_{\odot}</math> and <math> L_{\odot} </math> are the [[absolute magnitude]] and the luminosity of the Sun in chosen [[Photometric system|color-band]]<ref>Absolute magnitudes of the Sun in different color-bands can be obtained from {{harvtxt|Binney|Merrifield|1998}} or [http://www.ucolick.org/~cnaw/sun.html Absolute Magnitude of the Sun in Several Bands] {{webarchive|url=https://web.archive.org/web/20070718015507/http://www.ucolick.org/~cnaw/sun.html |date=2007-07-18 }}</ref> respectively.

Surface brightness can also be expressed in [[candela per square metre]] using the formula [value in cd/m<sup>2</sup>] = {{val|10.8e4}} × 10<sup>(−0.4×[value in mag/arcsec<sup>2</sup>])</sup>.