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class="vector-toc-numb">2</span> <span>Magnitudes and colour indices</span> </div> </a> <ul id="toc-Magnitudes_and_colour_indices-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Applications" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Applications"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Applications</span> </div> </a> <ul id="toc-Applications-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-CCD_photometry" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#CCD_photometry"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>CCD photometry</span> </div> </a> <button aria-controls="toc-CCD_photometry-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle CCD photometry subsection</span> </button> <ul id="toc-CCD_photometry-sublist" class="vector-toc-list"> <li id="toc-Calibrations" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Calibrations"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.1</span> <span>Calibrations</span> </div> </a> <ul id="toc-Calibrations-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Absolute_photometry" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Absolute_photometry"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2</span> <span>Absolute photometry</span> </div> </a> <ul id="toc-Absolute_photometry-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Relative_photometry" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Relative_photometry"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.3</span> <span>Relative photometry</span> </div> </a> <ul id="toc-Relative_photometry-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Differential_photometry" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Differential_photometry"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.4</span> <span>Differential photometry</span> </div> </a> <ul id="toc-Differential_photometry-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Surface_photometry" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Surface_photometry"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.5</span> <span>Surface photometry</span> </div> </a> <ul id="toc-Surface_photometry-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Forced_photometry" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Forced_photometry"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.6</span> <span>Forced photometry</span> </div> </a> <ul id="toc-Forced_photometry-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Software" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Software"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Software</span> </div> </a> <ul id="toc-Software-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Organizations" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Organizations"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Organizations</span> </div> </a> <ul id="toc-Organizations-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Photometry (astronomy)</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. Available in 40 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-40" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">40 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D9%82%D9%8A%D8%A7%D8%B3_%D8%B6%D9%88%D8%A6%D9%8A_%D9%81%D9%84%D9%83%D9%8A" title="قياس ضوئي فلكي – Arabic" lang="ar" hreflang="ar" data-title="قياس ضوئي فلكي" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-ast mw-list-item"><a href="https://ast.wikipedia.org/wiki/Fotometr%C3%ADa" title="Fotometría – Asturian" lang="ast" hreflang="ast" data-title="Fotometría" data-language-autonym="Asturianu" data-language-local-name="Asturian" class="interlanguage-link-target"><span>Asturianu</span></a></li><li class="interlanguage-link interwiki-az mw-list-item"><a href="https://az.wikipedia.org/wiki/Fotometriya_(astronomiya)" title="Fotometriya (astronomiya) – Azerbaijani" lang="az" hreflang="az" data-title="Fotometriya (astronomiya)" data-language-autonym="Azərbaycanca" data-language-local-name="Azerbaijani" class="interlanguage-link-target"><span>Azərbaycanca</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Fotometria" title="Fotometria – Catalan" lang="ca" hreflang="ca" data-title="Fotometria" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Astrofotometrie" title="Astrofotometrie – German" lang="de" hreflang="de" data-title="Astrofotometrie" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Fotomeetria_(astronoomia)" title="Fotomeetria (astronoomia) – Estonian" lang="et" hreflang="et" data-title="Fotomeetria (astronoomia)" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-el mw-list-item"><a href="https://el.wikipedia.org/wiki/%CE%A6%CF%89%CF%84%CE%BF%CE%BC%CE%B5%CF%84%CF%81%CE%AF%CE%B1" title="Φωτομετρία – Greek" lang="el" hreflang="el" data-title="Φωτομετρία" data-language-autonym="Ελληνικά" data-language-local-name="Greek" class="interlanguage-link-target"><span>Ελληνικά</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Fotometr%C3%ADa" title="Fotometría – Spanish" lang="es" hreflang="es" data-title="Fotometría" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/Fotometrio_(astronomio)" title="Fotometrio (astronomio) – Esperanto" lang="eo" hreflang="eo" data-title="Fotometrio (astronomio)" data-language-autonym="Esperanto" data-language-local-name="Esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Fotometria" title="Fotometria – Basque" lang="eu" hreflang="eu" data-title="Fotometria" data-language-autonym="Euskara" data-language-local-name="Basque" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D8%B4%DB%8C%D8%AF%D8%B3%D9%86%D8%AC%DB%8C_(%D8%A7%D8%AE%D8%AA%D8%B1%D8%B4%D9%86%D8%A7%D8%B3%DB%8C)" title="شیدسنجی (اخترشناسی) – Persian" lang="fa" hreflang="fa" data-title="شیدسنجی (اخترشناسی)" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Photom%C3%A9trie_(astronomie)" title="Photométrie (astronomie) – French" lang="fr" hreflang="fr" data-title="Photométrie (astronomie)" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/Fotometr%C3%ADa_(astronom%C3%ADa)" title="Fotometría (astronomía) – Galician" lang="gl" hreflang="gl" data-title="Fotometría (astronomía)" data-language-autonym="Galego" data-language-local-name="Galician" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EC%B8%A1%EA%B4%91%ED%95%99_(%EC%B2%9C%EB%AC%B8%ED%95%99)" title="측광학 (천문학) – Korean" lang="ko" hreflang="ko" data-title="측광학 (천문학)" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Fotometria_(astronomia)" title="Fotometria (astronomia) – Italian" lang="it" hreflang="it" data-title="Fotometria (astronomia)" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-lb mw-list-item"><a href="https://lb.wikipedia.org/wiki/Astrofotometrie" title="Astrofotometrie – Luxembourgish" lang="lb" hreflang="lb" data-title="Astrofotometrie" data-language-autonym="Lëtzebuergesch" data-language-local-name="Luxembourgish" class="interlanguage-link-target"><span>Lëtzebuergesch</span></a></li><li class="interlanguage-link interwiki-lt mw-list-item"><a href="https://lt.wikipedia.org/wiki/Astrofotometrija" title="Astrofotometrija – Lithuanian" lang="lt" hreflang="lt" data-title="Astrofotometrija" data-language-autonym="Lietuvių" data-language-local-name="Lithuanian" class="interlanguage-link-target"><span>Lietuvių</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/Fotometria_a_csillag%C3%A1szatban" title="Fotometria a csillagászatban – Hungarian" lang="hu" hreflang="hu" data-title="Fotometria a csillagászatban" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Fotometri_(astronomi)" title="Fotometri (astronomi) – Malay" lang="ms" hreflang="ms" data-title="Fotometri (astronomi)" data-language-autonym="Bahasa Melayu" data-language-local-name="Malay" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Fotometrie_(astronomie)" title="Fotometrie (astronomie) – Dutch" lang="nl" hreflang="nl" data-title="Fotometrie (astronomie)" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E6%B8%AC%E5%85%89_(%E5%A4%A9%E6%96%87)" title="測光 (天文) – Japanese" lang="ja" hreflang="ja" data-title="測光 (天文)" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Fotometri_(astronomi)" title="Fotometri (astronomi) – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Fotometri (astronomi)" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-nn mw-list-item"><a href="https://nn.wikipedia.org/wiki/Astrofotometri" title="Astrofotometri – Norwegian Nynorsk" lang="nn" hreflang="nn" data-title="Astrofotometri" data-language-autonym="Norsk nynorsk" data-language-local-name="Norwegian Nynorsk" class="interlanguage-link-target"><span>Norsk nynorsk</span></a></li><li class="interlanguage-link interwiki-oc mw-list-item"><a href="https://oc.wikipedia.org/wiki/Astrofotometria" title="Astrofotometria – Occitan" lang="oc" hreflang="oc" data-title="Astrofotometria" data-language-autonym="Occitan" data-language-local-name="Occitan" class="interlanguage-link-target"><span>Occitan</span></a></li><li class="interlanguage-link interwiki-uz mw-list-item"><a href="https://uz.wikipedia.org/wiki/Astrofotometriya" title="Astrofotometriya – Uzbek" lang="uz" hreflang="uz" data-title="Astrofotometriya" data-language-autonym="Oʻzbekcha / ўзбекча" data-language-local-name="Uzbek" class="interlanguage-link-target"><span>Oʻzbekcha / ўзбекча</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Fotometria_(astronomia)" title="Fotometria (astronomia) – Polish" lang="pl" hreflang="pl" data-title="Fotometria (astronomia)" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Fotometria_(astronomia)" title="Fotometria (astronomia) – Portuguese" lang="pt" hreflang="pt" data-title="Fotometria (astronomia)" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Fotometrie_(astronomie)" title="Fotometrie (astronomie) – Romanian" lang="ro" hreflang="ro" data-title="Fotometrie (astronomie)" data-language-autonym="Română" data-language-local-name="Romanian" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%A4%D0%BE%D1%82%D0%BE%D0%BC%D0%B5%D1%82%D1%80%D0%B8%D1%8F_(%D0%B0%D1%81%D1%82%D1%80%D0%BE%D0%BD%D0%BE%D0%BC%D0%B8%D1%8F)" title="Фотометрия (астрономия) – Russian" lang="ru" hreflang="ru" data-title="Фотометрия (астрономия)" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-simple mw-list-item"><a href="https://simple.wikipedia.org/wiki/Photometry_(astronomy)" title="Photometry (astronomy) – Simple English" lang="en-simple" hreflang="en-simple" data-title="Photometry (astronomy)" data-language-autonym="Simple English" data-language-local-name="Simple English" class="interlanguage-link-target"><span>Simple English</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Fotometria_(astron%C3%B3mia)" title="Fotometria (astronómia) – Slovak" lang="sk" hreflang="sk" data-title="Fotometria (astronómia)" data-language-autonym="Slovenčina" data-language-local-name="Slovak" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/Fotometrija_(astronomija)" title="Fotometrija (astronomija) – Serbian" lang="sr" hreflang="sr" data-title="Fotometrija (astronomija)" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Fotometria_(t%C3%A4htitiede)" title="Fotometria (tähtitiede) – Finnish" lang="fi" hreflang="fi" data-title="Fotometria (tähtitiede)" data-language-autonym="Suomi" data-language-local-name="Finnish" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B8%81%E0%B8%B2%E0%B8%A3%E0%B8%A7%E0%B8%B1%E0%B8%94%E0%B9%81%E0%B8%AA%E0%B8%87_(%E0%B8%94%E0%B8%B2%E0%B8%A3%E0%B8%B2%E0%B8%A8%E0%B8%B2%E0%B8%AA%E0%B8%95%E0%B8%A3%E0%B9%8C)" title="การวัดแสง (ดาราศาสตร์) – Thai" lang="th" hreflang="th" data-title="การวัดแสง (ดาราศาสตร์)" data-language-autonym="ไทย" data-language-local-name="Thai" class="interlanguage-link-target"><span>ไทย</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Fotometri_(astronomi)" title="Fotometri (astronomi) – Turkish" lang="tr" hreflang="tr" data-title="Fotometri (astronomi)" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%A4%D0%BE%D1%82%D0%BE%D0%BC%D0%B5%D1%82%D1%80%D1%96%D1%8F_(%D0%B0%D1%81%D1%82%D1%80%D0%BE%D0%BD%D0%BE%D0%BC%D1%96%D1%8F)" title="Фотометрія (астрономія) – Ukrainian" lang="uk" hreflang="uk" data-title="Фотометрія (астрономія)" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/Ph%C3%A9p_%C4%91o_s%C3%A1ng_(thi%C3%AAn_v%C4%83n_h%E1%BB%8Dc)" title="Phép đo sáng (thiên văn học) – Vietnamese" lang="vi" hreflang="vi" data-title="Phép đo sáng (thiên văn học)" data-language-autonym="Tiếng Việt" data-language-local-name="Vietnamese" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-wuu mw-list-item"><a href="https://wuu.wikipedia.org/wiki/%E5%85%89%E5%BA%A6%E6%B5%8B%E5%AE%9A%EF%BC%88%E5%A4%A9%E6%96%87%E5%AD%A6%EF%BC%89" title="光度测定（天文学） – Wu" lang="wuu" hreflang="wuu" data-title="光度测定（天文学）" data-language-autonym="吴语" data-language-local-name="Wu" class="interlanguage-link-target"><span>吴语</span></a></li><li class="interlanguage-link interwiki-zh-yue mw-list-item"><a href="https://zh-yue.wikipedia.org/wiki/%E5%85%89%E5%BA%A6%E5%AD%B8_(%E5%A4%A9%E6%96%87)" title="光度學 (天文) – Cantonese" lang="yue" hreflang="yue" 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src="//upload.wikimedia.org/wikipedia/commons/thumb/c/cb/Kepler_Mission_Space_Photometer_smaller.jpg/220px-Kepler_Mission_Space_Photometer_smaller.jpg" decoding="async" width="220" height="332" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/c/cb/Kepler_Mission_Space_Photometer_smaller.jpg 1.5x" data-file-width="320" data-file-height="483" /></a><figcaption><a href="/wiki/Kepler_Mission" class="mw-redirect" title="Kepler Mission">Kepler Mission</a> space photometer</figcaption></figure> <p>In <a href="/wiki/Astronomy" title="Astronomy">astronomy</a>, <b>photometry</b>, from <a href="/wiki/Ancient_Greek" title="Ancient Greek">Greek</a> <i><a href="https://en.wiktionary.org/wiki/photo-" class="extiw" title="wikt:photo-">photo-</a></i> ("light") and <i><a href="https://en.wiktionary.org/wiki/-metry" class="extiw" title="wikt:-metry">-metry</a></i> ("measure"), is a technique used in <a href="/wiki/Astronomy" title="Astronomy">astronomy</a> that is concerned with <a href="/wiki/Measurement" title="Measurement">measuring</a> the <a href="/wiki/Flux" title="Flux">flux</a> or <a href="/wiki/Intensity_(physics)" title="Intensity (physics)">intensity of light</a> radiated by <a href="/wiki/Astronomical_object" title="Astronomical object">astronomical objects</a>.<sup id="cite_ref-cv14_1-0" class="reference"><a href="#cite_note-cv14-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> This light is measured through a <a href="/wiki/Telescope" title="Telescope">telescope</a> using a <a href="/wiki/Photometer" title="Photometer">photometer</a>, often made using electronic devices such as a <a href="/wiki/CCD_photometry" class="mw-redirect" title="CCD photometry">CCD photometer</a> or a photoelectric photometer that converts light into an electric current by the <a href="/wiki/Photoelectric_effect" title="Photoelectric effect">photoelectric effect</a>. When calibrated against <a href="/wiki/Photometric-standard_star" title="Photometric-standard star">standard stars</a> (or other light sources) of known intensity and colour, photometers can measure the brightness or <a href="/wiki/Apparent_magnitude" title="Apparent magnitude">apparent magnitude</a> of celestial objects. </p><p>The methods used to perform photometry depend on the wavelength region under study. At its most basic, photometry is conducted by gathering light and passing it through specialized photometric <a href="/wiki/Optical_bandpass_filter" class="mw-redirect" title="Optical bandpass filter">optical bandpass filters</a>, and then capturing and recording the light energy with a photosensitive instrument. Standard sets of <a href="/wiki/Passband" title="Passband">passbands</a> (called a <a href="/wiki/Photometric_system" title="Photometric system">photometric system</a>) are defined to allow accurate comparison of observations.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> A more advanced technique is <a href="/wiki/Spectrophotometry" title="Spectrophotometry">spectrophotometry</a> that is measured with a <a href="/wiki/Optical_spectrometer" title="Optical spectrometer">spectrophotometer</a> and observes both the amount of radiation and its detailed <a href="/wiki/Electromagnetic_spectrum" title="Electromagnetic spectrum">spectral distribution</a>.<sup id="cite_ref-Kitchin1995_3-0" class="reference"><a href="#cite_note-Kitchin1995-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p><p>Photometry is also used in the observation of <a href="/wiki/Variable_star" title="Variable star">variable stars</a>,<sup id="cite_ref-Miles2007_4-0" class="reference"><a href="#cite_note-Miles2007-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> by various techniques such as, <i>differential photometry</i> that simultaneously measures the brightness of a target object and nearby stars in the starfield<sup id="cite_ref-Kern1986_5-0" class="reference"><a href="#cite_note-Kern1986-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> or <i>relative photometry</i> by comparing the brightness of the target object to stars with known fixed magnitudes.<sup id="cite_ref-Husarik2012_6-0" class="reference"><a href="#cite_note-Husarik2012-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> Using multiple bandpass filters with relative photometry is termed <i>absolute photometry</i>. A plot of magnitude against time produces a <a href="/wiki/Light_curve" title="Light curve">light curve</a>, yielding considerable information about the physical process causing the brightness changes.<sup id="cite_ref-north2014_7-0" class="reference"><a href="#cite_note-north2014-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> Precision photoelectric photometers can measure starlight around 0.001 magnitude.<sup id="cite_ref-Oxfordref_8-0" class="reference"><a href="#cite_note-Oxfordref-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> </p><p>The technique of <i>surface photometry</i> can also be used with extended objects like <a href="/wiki/Planet" title="Planet">planets</a>, <a href="/wiki/Comet" title="Comet">comets</a>, <a href="/wiki/Nebula" title="Nebula">nebulae</a> or <a href="/wiki/Galaxy" title="Galaxy">galaxies</a> that measures the apparent magnitude in terms of magnitudes per square arcsecond.<sup id="cite_ref-s"Palei1968"_9-0" class="reference"><a href="#cite_note-s"Palei1968"-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> Knowing the area of the object and the average intensity of light across the astronomical object determines the <a href="/wiki/Surface_brightness" title="Surface brightness">surface brightness</a> in terms of magnitudes per square arcsecond, while integrating the total light of the extended object can then calculate brightness in terms of its total magnitude, energy output or <a href="/wiki/Luminosity" title="Luminosity">luminosity</a> per unit surface area. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Methods">Methods</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photometry_(astronomy)&action=edit&section=1" title="Edit section: Methods"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Eta_Carinae_lightcurve_at_multiple_wavelengths_(1987_-_2014).png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f9/Eta_Carinae_lightcurve_at_multiple_wavelengths_%281987_-_2014%29.png/220px-Eta_Carinae_lightcurve_at_multiple_wavelengths_%281987_-_2014%29.png" decoding="async" width="220" height="164" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f9/Eta_Carinae_lightcurve_at_multiple_wavelengths_%281987_-_2014%29.png/330px-Eta_Carinae_lightcurve_at_multiple_wavelengths_%281987_-_2014%29.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/f9/Eta_Carinae_lightcurve_at_multiple_wavelengths_%281987_-_2014%29.png/440px-Eta_Carinae_lightcurve_at_multiple_wavelengths_%281987_-_2014%29.png 2x" data-file-width="1440" data-file-height="1075" /></a><figcaption><a href="/wiki/Eta_Carinae" title="Eta Carinae">Eta Carinae</a> <a href="/wiki/Light_curve" title="Light curve">light curve</a> in several different <a href="/wiki/Passband" title="Passband">passbands</a></figcaption></figure> <p>Astronomy was among the earliest applications of photometry. Modern <a href="/wiki/Photometer" title="Photometer">photometers</a> use specialised standard <a href="/wiki/Passband" title="Passband">passband</a> filters across the <a href="/wiki/Ultraviolet" title="Ultraviolet">ultraviolet</a>, <a href="/wiki/Visible_spectrum" title="Visible spectrum">visible</a>, and <a href="/wiki/Infrared" title="Infrared">infrared</a> wavelengths of the <a href="/wiki/Electromagnetic_spectrum" title="Electromagnetic spectrum">electromagnetic spectrum</a>.<sup id="cite_ref-Miles2007_4-1" class="reference"><a href="#cite_note-Miles2007-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> Any adopted set of filters with known <a href="/wiki/Optical_filter" title="Optical filter">light transmission properties</a> is called a <a href="/wiki/Photometric_system" title="Photometric system">photometric system</a>, and allows the establishment of particular properties about stars and other types of astronomical objects.<sup id="cite_ref-Bessell2005_10-0" class="reference"><a href="#cite_note-Bessell2005-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> Several important systems are regularly used, such as the <a href="/wiki/UBV_photometric_system" title="UBV photometric system">UBV system</a><sup id="cite_ref-JohnsonMorgan1953_11-0" class="reference"><a href="#cite_note-JohnsonMorgan1953-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> (or the extended UBVRI system<sup id="cite_ref-Lando2017_12-0" class="reference"><a href="#cite_note-Lando2017-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup>), <a href="/wiki/Infrared" title="Infrared">near infrared</a> JHK<sup id="cite_ref-Hewett2006_13-0" class="reference"><a href="#cite_note-Hewett2006-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> or the <a href="/wiki/Str%C3%B6mgren_photometric_system" title="Strömgren photometric system">Strömgren <i>uvbyβ</i> system</a>.<sup id="cite_ref-Bessell2005_10-1" class="reference"><a href="#cite_note-Bessell2005-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> </p><p>Historically, photometry in the near-<a href="/wiki/Infrared" title="Infrared">infrared</a> through short-wavelength <a href="/wiki/Ultra-violet" class="mw-redirect" title="Ultra-violet">ultra-violet</a> was done with a photoelectric photometer, an instrument that measured the light intensity of a single object by directing its light onto a photosensitive cell like a <a href="/wiki/Photomultiplier" title="Photomultiplier">photomultiplier tube</a>.<sup id="cite_ref-Miles2007_4-2" class="reference"><a href="#cite_note-Miles2007-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> These have largely been replaced with <a href="/wiki/Charge-coupled_device" title="Charge-coupled device">CCD</a> cameras that can simultaneously image multiple objects, although photoelectric photometers are still used in special situations,<sup id="cite_ref-ATNF2015_14-0" class="reference"><a href="#cite_note-ATNF2015-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> such as where fine time resolution is required.<sup id="cite_ref-Walker_15-0" class="reference"><a href="#cite_note-Walker-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Magnitudes_and_colour_indices">Magnitudes and colour indices</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photometry_(astronomy)&action=edit&section=2" title="Edit section: Magnitudes and colour indices"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Modern photometric methods define magnitudes and colours of astronomical objects using electronic photometers viewed through standard coloured bandpass filters. This differs from other expressions of <a href="/wiki/Apparent_magnitude" title="Apparent magnitude">apparent visual magnitude</a><sup id="cite_ref-north2014_7-1" class="reference"><a href="#cite_note-north2014-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> observed by the human eye or obtained by photography:<sup id="cite_ref-Miles2007_4-3" class="reference"><a href="#cite_note-Miles2007-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> that usually appear in older astronomical texts and catalogues. </p><p>Magnitudes measured by photometers in some commonplace photometric systems (UBV, UBVRI or JHK) are expressed with a capital letter, such as "V" (m<sub>V</sub>) or "B" (m<sub>B</sub>). Other magnitudes estimated by the human eye are expressed using lower case letters, such as "v", "b" or "p", etc.<sup id="cite_ref-macrobert2006_16-0" class="reference"><a href="#cite_note-macrobert2006-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> E.g. Visual magnitudes as m<sub>v</sub>,<sup id="cite_ref-Norton1989_17-0" class="reference"><a href="#cite_note-Norton1989-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> while <a href="/wiki/Photographic_magnitude" title="Photographic magnitude">photographic magnitudes</a> are m<sub>ph</sub> / m<sub>p</sub> or photovisual magnitudes m<sub>p</sub> or m<sub>pv</sub>.<sup id="cite_ref-Norton1989_17-1" class="reference"><a href="#cite_note-Norton1989-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Miles2007_4-4" class="reference"><a href="#cite_note-Miles2007-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> Hence, a 6th magnitude star might be stated as 6.0V, 6.0B, 6.0v or 6.0p. Because starlight is measured over a different range of wavelengths across the electromagnetic spectrum and are affected by different instrumental photometric sensitivities to light, they are not necessarily equivalent in numerical value.<sup id="cite_ref-macrobert2006_16-1" class="reference"><a href="#cite_note-macrobert2006-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> For example, apparent magnitude in the UBV system for the solar-like star <a href="/wiki/51_Pegasi" title="51 Pegasi">51 Pegasi</a><sup id="cite_ref-Strobell1996_18-0" class="reference"><a href="#cite_note-Strobell1996-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup> is 5.46V, 6.16B or 6.39U,<sup id="cite_ref-SIMBAD_19-0" class="reference"><a href="#cite_note-SIMBAD-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> corresponding to magnitudes observed through each of the visual 'V', blue 'B' or ultraviolet 'U' filters. </p><p>Magnitude differences between filters indicate colour differences and are related to temperature.<sup id="cite_ref-ATNF2002a_20-0" class="reference"><a href="#cite_note-ATNF2002a-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> Using B and V filters in the UBV system produces the B–V colour index.<sup id="cite_ref-ATNF2002a_20-1" class="reference"><a href="#cite_note-ATNF2002a-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> For <a href="/wiki/51_Pegasi" title="51 Pegasi">51 Pegasi</a>, the B–V = 6.16 – 5.46 = +0.70, suggesting a yellow coloured star that agrees with its G2IV spectral type.<sup id="cite_ref-Keenan1989_21-0" class="reference"><a href="#cite_note-Keenan1989-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-SIMBAD_19-1" class="reference"><a href="#cite_note-SIMBAD-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> Knowing the B–V results determines the star's surface temperature,<sup id="cite_ref-Luciuk2019_22-0" class="reference"><a href="#cite_note-Luciuk2019-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup> finding an effective surface temperature of 5768±8 K.<sup id="cite_ref-Mittag2016_23-0" class="reference"><a href="#cite_note-Mittag2016-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup> </p><p>Another important application of colour indices is graphically plotting star's apparent magnitude against the B–V colour index. This forms the important relationships found between sets of stars in <a href="/wiki/Hertzsprung-Russell_Diagram" class="mw-redirect" title="Hertzsprung-Russell Diagram">colour–magnitude diagrams</a>, which for stars is the observed version of the <a href="/wiki/Hertzsprung-Russell_diagram" class="mw-redirect" title="Hertzsprung-Russell diagram">Hertzsprung-Russell diagram</a>. Typically photometric measurements of multiple objects obtained through two filters will show, for example in an <a href="/wiki/Open_cluster" title="Open cluster">open cluster</a>,<sup id="cite_ref-Littlefair2015_24-0" class="reference"><a href="#cite_note-Littlefair2015-24"><span class="cite-bracket">[</span>24<span class="cite-bracket">]</span></a></sup> the comparative <a href="/wiki/Stellar_evolution" title="Stellar evolution">stellar evolution</a> between the component stars or to determine the cluster's relative age.<sup id="cite_ref-James2017_25-0" class="reference"><a href="#cite_note-James2017-25"><span class="cite-bracket">[</span>25<span class="cite-bracket">]</span></a></sup> </p><p>Due to the large number of different <a href="/wiki/Photometric_system" title="Photometric system">photometric systems</a> adopted by astronomers, there are many expressions of magnitudes and their indices.<sup id="cite_ref-Bessell2005_10-2" class="reference"><a href="#cite_note-Bessell2005-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> Each of these newer photometric systems, excluding UBV, UBVRI or JHK systems, assigns an upper or lower case letter to the filter used. For example, magnitudes used by <a href="/wiki/Gaia_(spacecraft)" title="Gaia (spacecraft)">Gaia</a> are 'G'<sup id="cite_ref-Jordi2010_26-0" class="reference"><a href="#cite_note-Jordi2010-26"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup> (with the blue and red photometric filters, G<sub>BP</sub> and G<sub>RP</sub><sup id="cite_ref-ESA2019_27-0" class="reference"><a href="#cite_note-ESA2019-27"><span class="cite-bracket">[</span>27<span class="cite-bracket">]</span></a></sup>) or the <a href="/wiki/Str%C3%B6mgren_photometric_system" title="Strömgren photometric system">Strömgren photometric system</a> having lower case letters of 'u', 'v', 'b', 'y', and two narrow and wide 'β' (<a href="/wiki/Balmer_series" title="Balmer series">Hydrogen-beta</a>) filters.<sup id="cite_ref-Bessell2005_10-3" class="reference"><a href="#cite_note-Bessell2005-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> Some photometric systems also have certain advantages. For example, <a href="/wiki/Str%C3%B6mgren_photometric_system" title="Strömgren photometric system">Strömgren photometry</a> can be used to measure the effects of reddening and <a href="/wiki/Extinction_(astronomy)" title="Extinction (astronomy)">interstellar extinction</a>.<sup id="cite_ref-Paunzen2015_28-0" class="reference"><a href="#cite_note-Paunzen2015-28"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup> Strömgren allows calculation of parameters from the <i>b</i> and <i>y</i> filters (colour index of <i>b</i> − <i>y</i>) without the effects of reddening, as the indices m <sub>1</sub> and c <sub>1</sub>.<sup id="cite_ref-Paunzen2015_28-1" class="reference"><a href="#cite_note-Paunzen2015-28"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Applications">Applications</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photometry_(astronomy)&action=edit&section=3" title="Edit section: Applications"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:AERONET_sunphotometer.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/7/7f/AERONET_sunphotometer.jpg/220px-AERONET_sunphotometer.jpg" decoding="async" width="220" height="197" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/7f/AERONET_sunphotometer.jpg/330px-AERONET_sunphotometer.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/7/7f/AERONET_sunphotometer.jpg 2x" data-file-width="412" data-file-height="368" /></a><figcaption><a href="/wiki/AERONET" title="AERONET">AERONET</a> photometer</figcaption></figure> <p>There are many astronomical applications used with photometric systems. Photometric measurements can be combined with the <a href="/wiki/Inverse-square_law" title="Inverse-square law">inverse-square law</a> to determine the <a href="/wiki/Luminosity" title="Luminosity">luminosity</a> of an object if its <a href="/wiki/Distance" title="Distance">distance</a> can be determined, or its distance if its luminosity is known. Other physical properties of an object, such as its <a href="/wiki/Temperature" title="Temperature">temperature</a> or chemical composition, may also be determined via broad or narrow-band spectrophotometry. </p><p>Photometry is also used to study the light variations of objects such as <a href="/wiki/Variable_star" title="Variable star">variable stars</a>, <a href="/wiki/Minor_planet" title="Minor planet">minor planets</a>, <a href="/wiki/Active_galactic_nucleus" title="Active galactic nucleus">active galactic nuclei</a> and <a href="/wiki/Supernova" title="Supernova">supernovae</a>,<sup id="cite_ref-north2014_7-2" class="reference"><a href="#cite_note-north2014-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> or to detect <a href="/wiki/Methods_of_detecting_extrasolar_planets" class="mw-redirect" title="Methods of detecting extrasolar planets">transiting extrasolar planets</a>. Measurements of these variations can be used, for example, to determine the <a href="/wiki/Orbital_period" title="Orbital period">orbital period</a> and the <a href="/wiki/Radius" title="Radius">radii</a> of the members of an <a href="/wiki/Binary_star" title="Binary star">eclipsing binary star</a> system, the <a href="/wiki/Rotation_period" class="mw-redirect" title="Rotation period">rotation period</a> of a minor planet or a star, or the total energy output of supernovae.<sup id="cite_ref-north2014_7-3" class="reference"><a href="#cite_note-north2014-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="CCD_photometry">CCD photometry</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photometry_(astronomy)&action=edit&section=4" title="Edit section: CCD photometry"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A CCD (<a href="/wiki/Charge-coupled_device" title="Charge-coupled device">charge-coupled device</a>) camera is essentially a grid of photometers, simultaneously measuring and recording the photons coming from all the sources in the field of view. Because each CCD image records the photometry of multiple objects at once, various forms of photometric extraction can be performed on the recorded data; typically relative, absolute, and differential. All three will require the extraction of the raw image <a href="/wiki/Magnitude_(astronomy)" title="Magnitude (astronomy)">magnitude</a> of the target object, and a known comparison object. The observed signal from an object will typically cover many <a href="/wiki/Pixel" title="Pixel">pixels</a> according to the <a href="/wiki/Point_spread_function" title="Point spread function">point spread function</a> (PSF) of the system. This broadening is due to both the optics in the telescope and the <a href="/wiki/Astronomical_seeing" title="Astronomical seeing">astronomical seeing</a>. When obtaining photometry from a <a href="/wiki/Point_source" title="Point source">point source</a>, the flux is measured by summing all the light recorded from the object and subtracting the light due to the sky.<sup id="cite_ref-mighell1999_29-0" class="reference"><a href="#cite_note-mighell1999-29"><span class="cite-bracket">[</span>29<span class="cite-bracket">]</span></a></sup> The simplest technique, known as aperture photometry, consists of summing the pixel counts within an aperture centered on the object and subtracting the product of the nearby average sky count per pixel and the number of pixels within the aperture.<sup id="cite_ref-mighell1999_29-1" class="reference"><a href="#cite_note-mighell1999-29"><span class="cite-bracket">[</span>29<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-laher2012_30-0" class="reference"><a href="#cite_note-laher2012-30"><span class="cite-bracket">[</span>30<span class="cite-bracket">]</span></a></sup> This will result in the raw flux value of the target object. When doing photometry in a very crowded field, such as a <a href="/wiki/Globular_cluster" title="Globular cluster">globular cluster</a>, where the profiles of stars overlap significantly, one must use de-blending techniques, such as PSF fitting to determine the individual flux values of the overlapping sources.<sup id="cite_ref-stetson1987_31-0" class="reference"><a href="#cite_note-stetson1987-31"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Calibrations">Calibrations</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photometry_(astronomy)&action=edit&section=5" title="Edit section: Calibrations"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>After determining the flux of an object in counts, the flux is normally converted into <a href="/wiki/Instrumental_magnitude" title="Instrumental magnitude">instrumental magnitude</a>. Then, the measurement is calibrated in some way. Which calibrations are used will depend in part on what type of photometry is being done. Typically, observations are processed for relative or differential photometry.<sup id="cite_ref-32" class="reference"><a href="#cite_note-32"><span class="cite-bracket">[</span>32<span class="cite-bracket">]</span></a></sup> Relative photometry is the measurement of the apparent brightness of multiple objects relative to each other. Absolute photometry is the measurement of the apparent brightness of an object on a <a href="/wiki/Photometric_system" title="Photometric system">standard photometric system</a>; these measurements can be compared with other absolute photometric measurements obtained with different telescopes or instruments. Differential photometry is the measurement of the difference in brightness of two objects. In most cases, differential photometry can be done with the highest <a href="/wiki/Accuracy_and_precision" title="Accuracy and precision">precision</a>, while absolute photometry is the most difficult to do with high precision. Also, accurate photometry is usually more difficult when the <a href="/wiki/Apparent_brightness" class="mw-redirect" title="Apparent brightness">apparent brightness</a> of the object is fainter. </p> <div class="mw-heading mw-heading3"><h3 id="Absolute_photometry">Absolute photometry</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photometry_(astronomy)&action=edit&section=6" title="Edit section: Absolute photometry"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1251242444">.mw-parser-output .ambox{border:1px solid #a2a9b1;border-left:10px solid #36c;background-color:#fbfbfb;box-sizing:border-box}.mw-parser-output .ambox+link+.ambox,.mw-parser-output .ambox+link+style+.ambox,.mw-parser-output .ambox+link+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+style+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+link+.ambox{margin-top:-1px}html body.mediawiki .mw-parser-output .ambox.mbox-small-left{margin:4px 1em 4px 0;overflow:hidden;width:238px;border-collapse:collapse;font-size:88%;line-height:1.25em}.mw-parser-output .ambox-speedy{border-left:10px solid #b32424;background-color:#fee7e6}.mw-parser-output .ambox-delete{border-left:10px solid #b32424}.mw-parser-output .ambox-content{border-left:10px solid #f28500}.mw-parser-output .ambox-style{border-left:10px solid #fc3}.mw-parser-output .ambox-move{border-left:10px solid #9932cc}.mw-parser-output .ambox-protection{border-left:10px solid #a2a9b1}.mw-parser-output .ambox .mbox-text{border:none;padding:0.25em 0.5em;width:100%}.mw-parser-output .ambox .mbox-image{border:none;padding:2px 0 2px 0.5em;text-align:center}.mw-parser-output .ambox .mbox-imageright{border:none;padding:2px 0.5em 2px 0;text-align:center}.mw-parser-output .ambox .mbox-empty-cell{border:none;padding:0;width:1px}.mw-parser-output .ambox .mbox-image-div{width:52px}@media(min-width:720px){.mw-parser-output .ambox{margin:0 10%}}@media print{body.ns-0 .mw-parser-output .ambox{display:none!important}}</style><table class="box-Unreferenced_section plainlinks metadata ambox ambox-content ambox-Unreferenced" role="presentation"><tbody><tr><td class="mbox-image"><div class="mbox-image-div"><span typeof="mw:File"><a href="/wiki/File:Question_book-new.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png" decoding="async" width="50" height="39" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/75px-Question_book-new.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/100px-Question_book-new.svg.png 2x" data-file-width="512" data-file-height="399" /></a></span></div></td><td class="mbox-text"><div class="mbox-text-span">This section <b>does not <a href="/wiki/Wikipedia:Citing_sources" title="Wikipedia:Citing sources">cite</a> any <a href="/wiki/Wikipedia:Verifiability" title="Wikipedia:Verifiability">sources</a></b>.<span class="hide-when-compact"> Please help <a href="/wiki/Special:EditPage/Photometry_(astronomy)" title="Special:EditPage/Photometry (astronomy)">improve this section</a> by <a href="/wiki/Help:Referencing_for_beginners" title="Help:Referencing for beginners">adding citations to reliable sources</a>. Unsourced material may be challenged and <a href="/wiki/Wikipedia:Verifiability#Burden_of_evidence" title="Wikipedia:Verifiability">removed</a>.</span> <span class="date-container"><i>(<span class="date">May 2019</span>)</i></span><span class="hide-when-compact"><i> (<small><a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove this message</a></small>)</i></span></div></td></tr></tbody></table> <p>To perform absolute photometry one must correct for differences between the effective passband through which an object is observed and the passband used to define the standard photometric system. This is often in addition to all of the other corrections discussed above. Typically this correction is done by observing the object(s) of interest through multiple filters and also observing a number of <a href="/wiki/Photometric_standard_stars" class="mw-redirect" title="Photometric standard stars">photometric standard stars</a>. If the standard stars cannot be observed simultaneously with the target(s), this correction must be done under photometric conditions, when the sky is cloudless and the extinction is a simple function of the <a href="/wiki/Airmass" class="mw-redirect" title="Airmass">airmass</a>. </p> <div class="mw-heading mw-heading3"><h3 id="Relative_photometry">Relative photometry</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photometry_(astronomy)&action=edit&section=7" title="Edit section: Relative photometry"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1251242444"><table class="box-Unreferenced_section plainlinks metadata ambox ambox-content ambox-Unreferenced" role="presentation"><tbody><tr><td class="mbox-image"><div class="mbox-image-div"><span typeof="mw:File"><a href="/wiki/File:Question_book-new.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png" decoding="async" width="50" height="39" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/75px-Question_book-new.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/100px-Question_book-new.svg.png 2x" data-file-width="512" data-file-height="399" /></a></span></div></td><td class="mbox-text"><div class="mbox-text-span">This section <b>does not <a href="/wiki/Wikipedia:Citing_sources" title="Wikipedia:Citing sources">cite</a> any <a href="/wiki/Wikipedia:Verifiability" title="Wikipedia:Verifiability">sources</a></b>.<span class="hide-when-compact"> Please help <a href="/wiki/Special:EditPage/Photometry_(astronomy)" title="Special:EditPage/Photometry (astronomy)">improve this section</a> by <a href="/wiki/Help:Referencing_for_beginners" title="Help:Referencing for beginners">adding citations to reliable sources</a>. Unsourced material may be challenged and <a href="/wiki/Wikipedia:Verifiability#Burden_of_evidence" title="Wikipedia:Verifiability">removed</a>.</span> <span class="date-container"><i>(<span class="date">May 2019</span>)</i></span><span class="hide-when-compact"><i> (<small><a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove this message</a></small>)</i></span></div></td></tr></tbody></table> <p>To perform relative photometry, one compares the instrument magnitude of the object to a known comparison object, and then corrects the measurements for spatial variations in the sensitivity of the instrument and the atmospheric extinction. This is often in addition to correcting for their temporal variations, particularly when the objects being compared are too far apart on the sky to be observed simultaneously.<sup id="cite_ref-Husarik2012_6-1" class="reference"><a href="#cite_note-Husarik2012-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> When doing the calibration from an image that contains both the target and comparison objects in close proximity, and using a photometric filter that matches the catalog magnitude of the comparison object most of the measurement variations decrease to null. </p> <div class="mw-heading mw-heading3"><h3 id="Differential_photometry">Differential photometry</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photometry_(astronomy)&action=edit&section=8" title="Edit section: Differential photometry"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1251242444"><table class="box-Unreferenced_section plainlinks metadata ambox ambox-content ambox-Unreferenced" role="presentation"><tbody><tr><td class="mbox-image"><div class="mbox-image-div"><span typeof="mw:File"><a href="/wiki/File:Question_book-new.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png" decoding="async" width="50" height="39" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/75px-Question_book-new.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/100px-Question_book-new.svg.png 2x" data-file-width="512" data-file-height="399" /></a></span></div></td><td class="mbox-text"><div class="mbox-text-span">This section <b>does not <a href="/wiki/Wikipedia:Citing_sources" title="Wikipedia:Citing sources">cite</a> any <a href="/wiki/Wikipedia:Verifiability" title="Wikipedia:Verifiability">sources</a></b>.<span class="hide-when-compact"> Please help <a href="/wiki/Special:EditPage/Photometry_(astronomy)" title="Special:EditPage/Photometry (astronomy)">improve this section</a> by <a href="/wiki/Help:Referencing_for_beginners" title="Help:Referencing for beginners">adding citations to reliable sources</a>. Unsourced material may be challenged and <a href="/wiki/Wikipedia:Verifiability#Burden_of_evidence" title="Wikipedia:Verifiability">removed</a>.</span> <span class="date-container"><i>(<span class="date">May 2019</span>)</i></span><span class="hide-when-compact"><i> (<small><a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove this message</a></small>)</i></span></div></td></tr></tbody></table> <p>Differential photometry is the simplest of the calibrations and most useful for time series observations.<sup id="cite_ref-Kern1986_5-1" class="reference"><a href="#cite_note-Kern1986-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> When using CCD photometry, both the target and comparison objects are observed at the same time, with the same filters, using the same instrument, and viewed through the same optical path. Most of the observational variables drop out and the differential magnitude is simply the difference between the instrument magnitude of the target object and the comparison object (∆Mag = C Mag – T Mag). This is very useful when plotting the change in magnitude over time of a target object, and is usually compiled into a <a href="/wiki/Light_curve" title="Light curve">light curve</a>.<sup id="cite_ref-Kern1986_5-2" class="reference"><a href="#cite_note-Kern1986-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Surface_photometry">Surface photometry</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photometry_(astronomy)&action=edit&section=9" title="Edit section: Surface photometry"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>For spatially extended objects such as <a href="/wiki/Galaxy" title="Galaxy">galaxies</a>, it is often of interest to measure the spatial distribution of brightness within the galaxy rather than simply measuring the galaxy's total brightness. An object's <a href="/wiki/Surface_brightness" title="Surface brightness">surface brightness</a> is its brightness per unit <a href="/wiki/Solid_angle" title="Solid angle">solid angle</a> as seen in projection on the sky, and measurement of surface brightness is known as surface photometry.<sup id="cite_ref-s"Palei1968"_9-1" class="reference"><a href="#cite_note-s"Palei1968"-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> A common application would be measurement of a galaxy's surface brightness profile, meaning its surface brightness as a function of distance from the galaxy's center. For small solid angles, a useful unit of solid angle is the square <a href="/wiki/Minute_and_second_of_arc" title="Minute and second of arc">arcsecond</a>, and surface brightness is often expressed in magnitudes per square arcsecond. The diameter of galaxies are often defined by the size of the 25th magnitude <a href="/wiki/Isophote" title="Isophote">isophote</a> in the blue B-band.<sup id="cite_ref-33" class="reference"><a href="#cite_note-33"><span class="cite-bracket">[</span>33<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Forced_photometry">Forced photometry</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photometry_(astronomy)&action=edit&section=10" title="Edit section: Forced photometry"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In <b>forced photometry</b>, measurements are conducted at a specified <i>location</i> rather than for a specified <i>object</i>. It is "forced" in the sense that a measurement can be taken even if there is no object visible (in the <a href="/wiki/Spectral_band" title="Spectral band">spectral band</a> of interest) in the location being observed. Forced photometry allows extracting a magnitude, or an upper limit for the magnitude, at a chosen sky location.<sup id="cite_ref-34" class="reference"><a href="#cite_note-34"><span class="cite-bracket">[</span>34<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-35" class="reference"><a href="#cite_note-35"><span class="cite-bracket">[</span>35<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-36" class="reference"><a href="#cite_note-36"><span class="cite-bracket">[</span>36<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Software">Software</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photometry_(astronomy)&action=edit&section=11" title="Edit section: Software"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A number of free computer programs are available for synthetic aperture photometry and PSF-fitting photometry. </p><p>SExtractor<sup id="cite_ref-37" class="reference"><a href="#cite_note-37"><span class="cite-bracket">[</span>37<span class="cite-bracket">]</span></a></sup> and <a href="/wiki/Aperture_Photometry_Tool" title="Aperture Photometry Tool">Aperture Photometry Tool</a><sup id="cite_ref-38" class="reference"><a href="#cite_note-38"><span class="cite-bracket">[</span>38<span class="cite-bracket">]</span></a></sup> are popular examples for aperture photometry. The former is geared towards reduction of large scale galaxy-survey data, and the latter has a graphical user interface (GUI) suitable for studying individual images. DAOPHOT is recognized as the best software for PSF-fitting photometry.<sup id="cite_ref-stetson1987_31-1" class="reference"><a href="#cite_note-stetson1987-31"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Organizations">Organizations</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photometry_(astronomy)&action=edit&section=12" title="Edit section: Organizations"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>There are a number of organizations, from professional to amateur, that gather and share photometric data and make it available on-line. Some sites gather the data primarily as a resource for other researchers (ex. AAVSO) and some solicit contributions of data for their own research (ex. CBA): </p> <ul><li>American Association of Variable Star Observers (<a href="/wiki/American_Association_of_Variable_Star_Observers" title="American Association of Variable Star Observers">AAVSO</a>).<sup id="cite_ref-39" class="reference"><a href="#cite_note-39"><span class="cite-bracket">[</span>39<span class="cite-bracket">]</span></a></sup></li> <li>Astronomyonline.org<sup id="cite_ref-40" class="reference"><a href="#cite_note-40"><span class="cite-bracket">[</span>40<span class="cite-bracket">]</span></a></sup></li> <li>Center for Backyard Astrophysics (CBA).<sup id="cite_ref-41" class="reference"><a href="#cite_note-41"><span class="cite-bracket">[</span>41<span class="cite-bracket">]</span></a></sup></li></ul> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photometry_(astronomy)&action=edit&section=13" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Albedo" title="Albedo">Albedo</a></li> <li><a href="/wiki/Aperture_Photometry_Tool" title="Aperture Photometry Tool">Aperture Photometry Tool</a> - Software</li> <li><a href="/wiki/Bidirectional_reflectance_distribution_function" title="Bidirectional reflectance distribution function">Bidirectional reflectance distribution function</a></li> <li><a href="/wiki/Hapke_parameters" title="Hapke parameters">Hapke parameters</a></li> <li><a href="/wiki/Radiometry" title="Radiometry">Radiometry</a></li> <li><a href="/wiki/Redshift_survey" title="Redshift survey">Redshift survey</a></li> <li><a href="/wiki/Spectroscopy" title="Spectroscopy">Spectroscopy</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photometry_(astronomy)&action=edit&section=14" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-cv14-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-cv14_1-0">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFCasagrandeVandenBerg2014" class="citation journal cs1">Casagrande, Luca; VandenBerg, Don A (2014). <a rel="nofollow" class="external text" href="https://doi.org/10.1093%2Fmnras%2Fstu1476">"Synthetic stellar photometry - General considerations and new transformations for broad-band systems"</a>. <i>Monthly Notices of the Royal Astronomical Society</i>. <b>444</b> (1). <a href="/wiki/Oxford_University_Press" title="Oxford University Press">Oxford University Press</a>: 392–419. <a href="/wiki/ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/1407.6095">1407.6095</a></span>. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2014MNRAS.444..392C">2014MNRAS.444..392C</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1093%2Fmnras%2Fstu1476">10.1093/mnras/stu1476</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Monthly+Notices+of+the+Royal+Astronomical+Society&rft.atitle=Synthetic+stellar+photometry+-+General+considerations+and+new+transformations+for+broad-band+systems&rft.volume=444&rft.issue=1&rft.pages=392-419&rft.date=2014&rft_id=info%3Aarxiv%2F1407.6095&rft_id=info%3Adoi%2F10.1093%2Fmnras%2Fstu1476&rft_id=info%3Abibcode%2F2014MNRAS.444..392C&rft.aulast=Casagrande&rft.aufirst=Luca&rft.au=VandenBerg%2C+Don+A&rft_id=https%3A%2F%2Fdoi.org%2F10.1093%252Fmnras%252Fstu1476&rfr_id=info%3Asid%2Fen.wikipedia.org%3APhotometry+%28astronomy%29" class="Z3988"></span></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBrian_D._Warner2016" class="citation book cs1">Brian D. Warner (20 June 2016). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=fu56DAAAQBAJ"><i>A Practical Guide to Lightcurve Photometry and Analysis</i></a>. Springer. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-3-319-32750-1" title="Special:BookSources/978-3-319-32750-1"><bdi>978-3-319-32750-1</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=A+Practical+Guide+to+Lightcurve+Photometry+and+Analysis&rft.pub=Springer&rft.date=2016-06-20&rft.isbn=978-3-319-32750-1&rft.au=Brian+D.+Warner&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3Dfu56DAAAQBAJ&rfr_id=info%3Asid%2Fen.wikipedia.org%3APhotometry+%28astronomy%29" class="Z3988"></span></span> </li> <li id="cite_note-Kitchin1995-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-Kitchin1995_3-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFC.R._Kitchin1995" class="citation book cs1">C.R. 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(2007). "A light history of photometry: from Hipparchus to the Hubble Space Telescope". <i>Journal of the British Astronomical Association</i>. <b>117</b>: 178–186. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2007JBAA..117..172M">2007JBAA..117..172M</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Journal+of+the+British+Astronomical+Association&rft.atitle=A+light+history+of+photometry%3A+from+Hipparchus+to+the+Hubble+Space+Telescope&rft.volume=117&rft.pages=178-186&rft.date=2007&rft_id=info%3Abibcode%2F2007JBAA..117..172M&rft.aulast=Miles&rft.aufirst=R.&rfr_id=info%3Asid%2Fen.wikipedia.org%3APhotometry+%28astronomy%29" class="Z3988"></span></span> </li> <li id="cite_note-Kern1986-5"><span class="mw-cite-backlink">^ <a href="#cite_ref-Kern1986_5-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Kern1986_5-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Kern1986_5-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFKernBookmyer1986" class="citation journal cs1">Kern, J.~R.; Bookmyer, B.~B. (1986). <a rel="nofollow" class="external text" href="https://doi.org/10.1086%2F131940">"Differential photometry of HDE 310376, a rapid variable star"</a>. <i>Publications of the Astronomical Society of the Pacific</i>. <b>98</b>: 1336–1341. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1986PASP...98.1336K">1986PASP...98.1336K</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1086%2F131940">10.1086/131940</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Publications+of+the+Astronomical+Society+of+the+Pacific&rft.atitle=Differential+photometry+of+HDE+310376%2C+a+rapid+variable+star&rft.volume=98&rft.pages=1336-1341&rft.date=1986&rft_id=info%3Adoi%2F10.1086%2F131940&rft_id=info%3Abibcode%2F1986PASP...98.1336K&rft.aulast=Kern&rft.aufirst=J.~R.&rft.au=Bookmyer%2C+B.~B.&rft_id=https%3A%2F%2Fdoi.org%2F10.1086%252F131940&rfr_id=info%3Asid%2Fen.wikipedia.org%3APhotometry+%28astronomy%29" class="Z3988"></span></span> </li> <li id="cite_note-Husarik2012-6"><span class="mw-cite-backlink">^ <a href="#cite_ref-Husarik2012_6-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Husarik2012_6-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHusárik2012" class="citation journal cs1">Husárik, M. 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S.</a>; Gallagher, J. S. III (2000). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=tzNF79roUfoC"><i>Galaxies in the Universe: An Introduction</i></a>. <a href="/wiki/Cambridge_University_Press" title="Cambridge University Press">Cambridge University Press</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-521-59740-1" title="Special:BookSources/978-0-521-59740-1"><bdi>978-0-521-59740-1</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20210324072126/https://books.google.com/books?id=tzNF79roUfoC">Archived</a> from the original on March 24, 2021<span class="reference-accessdate">. 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"Processing GOTO survey data with the Rubin Observatory LSST Science Pipelines II: Forced Photometry and lightcurves". <i>Publications of the Astronomical Society of Australia</i>. <b>38</b>. <a href="/wiki/ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/2105.05128">2105.05128</a></span>. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2021PASA...38...25M">2021PASA...38...25M</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1017%2Fpasa.2021.19">10.1017/pasa.2021.19</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Publications+of+the+Astronomical+Society+of+Australia&rft.atitle=Processing+GOTO+survey+data+with+the+Rubin+Observatory+LSST+Science+Pipelines+II%3A+Forced+Photometry+and+lightcurves&rft.volume=38&rft.date=2021&rft_id=info%3Aarxiv%2F2105.05128&rft_id=info%3Adoi%2F10.1017%2Fpasa.2021.19&rft_id=info%3Abibcode%2F2021PASA...38...25M&rft.aulast=Makrygianni&rft.aufirst=L.&rft.au=Mullaney%2C+J.&rft.au=Dhillon%2C+V.&rfr_id=info%3Asid%2Fen.wikipedia.org%3APhotometry+%28astronomy%29" class="Z3988"></span></span> </li> <li id="cite_note-36"><span class="mw-cite-backlink"><b><a href="#cite_ref-36">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBurenin2022" class="citation journal cs1">Burenin, R. 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title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Astronomy+Letters&rft.atitle=Forced+Photometry+for+Pan-STARRS1+Objects+Based+on+WISE+Data&rft.volume=48&rft.issue=3&rft.pages=153-162&rft.date=2022&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A253022975%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1134%2FS1063773722030021&rft_id=info%3Abibcode%2F2022AstL...48..153B&rft.aulast=Burenin&rft.aufirst=R.+A.&rft_id=https%3A%2F%2Flink.springer.com%2Farticle%2F10.1134%2FS1063773722030021&rfr_id=info%3Asid%2Fen.wikipedia.org%3APhotometry+%28astronomy%29" class="Z3988"></span></span> </li> <li id="cite_note-37"><span class="mw-cite-backlink"><b><a href="#cite_ref-37">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.astromatic.net/software/sextractor">"SExtractor<span class="nowrap"> </span>– Astromatic.net"</a>. <i>www.astromatic.net</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.astromatic.net&rft.atitle=SExtractor%3Cspan+class%3D%22nowrap%22%3E+%3C%2Fspan%3E%E2%80%93+Astromatic.net&rft_id=http%3A%2F%2Fwww.astromatic.net%2Fsoftware%2Fsextractor&rfr_id=info%3Asid%2Fen.wikipedia.org%3APhotometry+%28astronomy%29" class="Z3988"></span></span> </li> <li id="cite_note-38"><span class="mw-cite-backlink"><b><a href="#cite_ref-38">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.aperturephotometry.org">"Aperture Photometry Tool: Home"</a>. <i>www.aperturephotometry.org</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.aperturephotometry.org&rft.atitle=Aperture+Photometry+Tool%3A+Home&rft_id=http%3A%2F%2Fwww.aperturephotometry.org&rfr_id=info%3Asid%2Fen.wikipedia.org%3APhotometry+%28astronomy%29" class="Z3988"></span></span> </li> <li id="cite_note-39"><span class="mw-cite-backlink"><b><a href="#cite_ref-39">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.aavso.org">"aavso.org"</a>. <i>www.aavso.org</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.aavso.org&rft.atitle=aavso.org&rft_id=http%3A%2F%2Fwww.aavso.org&rfr_id=info%3Asid%2Fen.wikipedia.org%3APhotometry+%28astronomy%29" class="Z3988"></span></span> </li> <li id="cite_note-40"><span class="mw-cite-backlink"><b><a href="#cite_ref-40">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://astronomyonline.org/Exoplanets/AmateurDetection.asp">"Exoplanet - Amateur Detection"</a>. <i>astronomyonline.org</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=astronomyonline.org&rft.atitle=Exoplanet+-+Amateur+Detection&rft_id=http%3A%2F%2Fastronomyonline.org%2FExoplanets%2FAmateurDetection.asp&rfr_id=info%3Asid%2Fen.wikipedia.org%3APhotometry+%28astronomy%29" class="Z3988"></span></span> </li> <li id="cite_note-41"><span class="mw-cite-backlink"><b><a href="#cite_ref-41">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.cbastro.org">"CBA @ cbastro.org - Center for Backyard Astrophysics"</a>. <i>www.cbastro.org</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.cbastro.org&rft.atitle=CBA+%40+cbastro.org+-+Center+for+Backyard+Astrophysics&rft_id=http%3A%2F%2Fwww.cbastro.org&rfr_id=info%3Asid%2Fen.wikipedia.org%3APhotometry+%28astronomy%29" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photometry_(astronomy)&action=edit&section=15" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.atnf.csiro.au/outreach//education/senior/astrophysics/photometry_links.html">"Photometry Links"</a>. <i>CSIRO : Australian Telescope National Facility</i>. 2019-05-08.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=CSIRO+%3A+Australian+Telescope+National+Facility&rft.atitle=Photometry+Links&rft.date=2019-05-08&rft_id=https%3A%2F%2Fwww.atnf.csiro.au%2Foutreach%2F%2Feducation%2Fsenior%2Fastrophysics%2Fphotometry_links.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3APhotometry+%28astronomy%29" class="Z3988"></span></li></ul> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output 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astronomy">Timeline</a></span></li></ul></li> <li><span class="nowrap"><a href="/wiki/Astronomer" title="Astronomer">Astronomer</a></span></li> <li><span class="nowrap"><a href="/wiki/Astronomical_symbols" title="Astronomical symbols">Astronomical symbols</a></span></li> <li><span class="nowrap"><a href="/wiki/Astronomical_object" title="Astronomical object">Astronomical object</a></span></li> <li><span class="nowrap"><a href="/wiki/Glossary_of_astronomy" title="Glossary of astronomy">Glossary</a></span></li> <li><span class="nowrap"><a href="/wiki/List_of_topics_in_space" title="List of topics in space">... in space</a></span></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="text-align: center;;width:1%">Astronomy by</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%;font-weight:normal; text-align: center;">Manner</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><span class="nowrap"><a href="/wiki/Amateur_astronomy" title="Amateur astronomy">Amateur</a></span></li> <li><span class="nowrap"><a href="/wiki/Observational_astronomy" title="Observational astronomy">Observational</a></span></li> <li><span class="nowrap"><a href="/wiki/Sidewalk_astronomy" title="Sidewalk astronomy">Sidewalk</a></span></li> <li><span class="nowrap"><a href="/wiki/Space_telescope" title="Space telescope">Space telescope</a></span></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;font-weight:normal; text-align: center;">Celestial subject</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><span class="nowrap"><a href="/wiki/Galactic_astronomy" title="Galactic astronomy">Galactic</a> / <a href="/wiki/Extragalactic_astronomy" title="Extragalactic astronomy">Extragalactic</a></span></li> <li><span class="nowrap"><a href="/wiki/Solar_System" title="Solar System">Local system</a></span> <ul><li><span class="nowrap"><a href="/wiki/Sun" title="Sun">Solar</a></span></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;font-weight:normal; text-align: center;">EM methods</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><span class="nowrap"><a href="/wiki/Radio_astronomy" title="Radio astronomy">Radio</a></span></li> <li><span class="nowrap"><a href="/wiki/Submillimetre_astronomy" title="Submillimetre astronomy">Submillimetre</a></span></li> <li><span class="nowrap"><a href="/wiki/Infrared_astronomy" title="Infrared astronomy">Infrared</a> (<span style="font-size:85%;"><a href="/wiki/Far-infrared_astronomy" title="Far-infrared astronomy">Far-infrared</a></span>)</span></li> <li><span class="nowrap"><a href="/wiki/Visible-light_astronomy" title="Visible-light astronomy">Visible-light <span style="font-size:85%;">(optical)</span></a></span></li> <li><span class="nowrap"><a href="/wiki/Ultraviolet_astronomy" title="Ultraviolet astronomy">Ultraviolet</a></span></li> <li><span class="nowrap"><a href="/wiki/X-ray_astronomy" title="X-ray astronomy">X-ray</a></span> <ul><li><span class="nowrap"><a href="/wiki/History_of_X-ray_astronomy" title="History of X-ray astronomy">History</a></span></li></ul></li> <li><span class="nowrap"><a href="/wiki/Gamma-ray_astronomy" title="Gamma-ray astronomy">Gamma-ray</a></span></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;font-weight:normal; text-align: center;">Other methods</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><span class="nowrap"><a href="/wiki/Neutrino_astronomy" title="Neutrino astronomy">Neutrino</a></span></li> <li><span class="nowrap"><a href="/wiki/Cosmic_ray_astronomy" title="Cosmic ray astronomy">Cosmic rays</a></span></li> <li><span class="nowrap"><a href="/wiki/Gravitational-wave_astronomy" title="Gravitational-wave astronomy">Gravitational radiation</a></span></li> <li><span class="nowrap"><a href="/wiki/High-energy_astronomy" title="High-energy astronomy">High-energy</a></span></li> <li><span class="nowrap"><a href="/wiki/Radar_astronomy" title="Radar astronomy">Radar</a></span></li> <li><span class="nowrap"><a href="/wiki/Spherical_astronomy" title="Spherical astronomy">Spherical</a></span></li> <li><span class="nowrap"><a href="/wiki/Multi-messenger_astronomy" title="Multi-messenger astronomy">Multi-messenger</a></span></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;font-weight:normal; text-align: center;"><a href="/wiki/Cultural_astronomy" title="Cultural astronomy">Culture</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><span class="nowrap"><a href="/wiki/Australian_Aboriginal_astronomy" title="Australian Aboriginal astronomy">Australian Aboriginal</a></span></li> <li><span class="nowrap"><a href="/wiki/Babylonian_astronomy" title="Babylonian astronomy">Babylonian</a></span></li> <li><span class="nowrap"><a href="/wiki/Chinese_astronomy" title="Chinese astronomy">Chinese</a></span></li> <li><span class="nowrap"><a href="/wiki/Egyptian_astronomy" title="Egyptian astronomy">Egyptian</a></span></li> <li><span class="nowrap"><a href="/wiki/Ancient_Greek_astronomy" title="Ancient Greek astronomy">Greek</a></span></li> <li><span class="nowrap"><a href="/wiki/Hebrew_astronomy" title="Hebrew astronomy">Hebrew</a></span></li> <li><span class="nowrap"><a href="/wiki/Indian_astronomy" title="Indian astronomy">Indian</a></span></li> <li><span class="nowrap"><a href="/wiki/Inuit_astronomy" title="Inuit astronomy">Inuit</a></span></li> <li><span class="nowrap"><a href="/wiki/Maya_astronomy" title="Maya astronomy">Maya</a></span></li> <li><span class="nowrap"><a href="/wiki/Astronomy_in_the_medieval_Islamic_world" title="Astronomy in the medieval Islamic world">Medieval Islamic</a></span></li> <li><span class="nowrap"><a href="/wiki/Persian_astronomy" title="Persian astronomy">Persian</a></span></li> <li><span class="nowrap"><a href="/wiki/Astronomy_in_Serbia" title="Astronomy in Serbia">Serbian</a></span> <ul><li><span class="nowrap"><a href="/wiki/Serbian_folk_astronomy" title="Serbian folk astronomy">folk</a></span></li></ul></li> <li><span class="nowrap"><a href="/wiki/Tibetan_astronomy" title="Tibetan astronomy">Tibetan</a></span></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="text-align: center;;width:1%"><a href="/wiki/Optical_telescope" title="Optical telescope">Optical<br />telescopes</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><span class="nowrap"><a href="/wiki/List_of_optical_telescopes" title="List of optical telescopes">List</a></span></li> <li><span class="nowrap"><a href="/wiki/Category:Telescopes" title="Category:Telescopes">Category</a></span></li> <li><span class="nowrap"><a href="/wiki/Extremely_large_telescope" title="Extremely large telescope">Extremely large telescope</a></span></li> <li><span class="nowrap"><a href="/wiki/Extremely_Large_Telescope" title="Extremely Large Telescope">Extremely Large Telescope</a></span></li> <li><span class="nowrap"><a href="/wiki/Gran_Telescopio_Canarias" title="Gran Telescopio Canarias">Gran Telescopio Canarias</a></span></li> <li><span class="nowrap"><a href="/wiki/Hale_Telescope" title="Hale Telescope">Hale Telescope</a></span></li> <li><span class="nowrap"><a href="/wiki/Hubble_Space_Telescope" title="Hubble Space Telescope">Hubble Space Telescope</a></span></li> <li><span class="nowrap"><a href="/wiki/W._M._Keck_Observatory" title="W. M. Keck Observatory">Keck Observatory</a></span></li> <li><span class="nowrap"><a href="/wiki/Large_Binocular_Telescope" title="Large Binocular Telescope">Large Binocular Telescope</a></span></li> <li><span class="nowrap"><a href="/wiki/Southern_African_Large_Telescope" title="Southern African Large Telescope">Southern African Large Telescope</a></span></li> <li><span class="nowrap"><a href="/wiki/Very_Large_Telescope" title="Very Large Telescope">Very Large Telescope</a></span></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="text-align: center;;width:1%">Related</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><span class="nowrap"><a href="/wiki/Archaeoastronomy" title="Archaeoastronomy">Archaeoastronomy</a></span></li> <li><span class="nowrap"><a href="/wiki/Astrobiology" title="Astrobiology">Astrobiology</a></span></li> <li><span class="nowrap"><a href="/wiki/Astrochemistry" title="Astrochemistry">Astrochemistry</a></span></li> <li><span class="nowrap"><a href="/wiki/Astroinformatics" title="Astroinformatics">Astroinformatics</a></span></li> <li><span class="nowrap"><a href="/wiki/Astrophysics" title="Astrophysics">Astrophysics</a></span></li> <li><span class="nowrap"><a href="/wiki/Astrology_and_astronomy" title="Astrology and astronomy">Astrology and astronomy</a></span></li> <li><span class="nowrap"><a href="/wiki/Astrometry" title="Astrometry">Astrometry</a></span></li> <li><span class="nowrap"><i><a href="/wiki/Astronomers_Monument" title="Astronomers Monument">Astronomers Monument</a></i></span></li> <li><span class="nowrap"><a href="/wiki/Astroparticle_physics" title="Astroparticle physics">Astroparticle physics</a></span></li> <li><span class="nowrap"><a href="/wiki/Binoculars" title="Binoculars">Binoculars</a></span></li> <li><span class="nowrap"><a href="/wiki/Constellation" title="Constellation">Constellation</a></span> <ul><li><span class="nowrap"><a href="/wiki/IAU_designated_constellations" title="IAU designated constellations">IAU</a></span></li></ul></li> <li><span class="nowrap"><a class="mw-selflink selflink">Photometry</a></span></li> <li><span class="nowrap"><a href="/wiki/Planetarium" title="Planetarium">Planetarium</a></span></li> <li><span class="nowrap"><a href="/wiki/Planetary_geology" title="Planetary geology">Planetary geology</a></span></li> <li><span class="nowrap"><a href="/wiki/Physical_cosmology" title="Physical cosmology">Physical cosmology</a></span></li> <li><span class="nowrap"><a href="/wiki/Quantum_cosmology" title="Quantum cosmology">Quantum cosmology</a></span></li> <li><span class="nowrap"><a href="/wiki/List_of_astronomers" title="List of astronomers">List of astronomers</a></span> <ul><li><span class="nowrap"><a href="/wiki/List_of_French_astronomers" title="List of French astronomers">French</a></span></li> <li><span class="nowrap"><a href="/wiki/Astronomy_in_the_medieval_Islamic_world#Notable_astronomers" title="Astronomy in the medieval Islamic world">Medieval Islamic</a></span></li> <li><span class="nowrap"><a href="/wiki/List_of_Russian_astronomers_and_astrophysicists" title="List of Russian astronomers and astrophysicists">Russian</a></span></li> <li><span class="nowrap"><a href="/wiki/List_of_women_astronomers" title="List of women astronomers">Women</a></span></li></ul></li> <li><span class="nowrap"><a href="/wiki/Telescope" title="Telescope">Telescope</a></span> <ul><li><span class="nowrap"><a href="/wiki/X-ray_telescope" title="X-ray telescope">X-ray telescope</a></span></li> <li><span class="nowrap"><a href="/wiki/History_of_the_telescope" title="History of the telescope">history</a></span></li> <li><span class="nowrap"><a href="/wiki/Lists_of_telescopes" title="Lists of telescopes">lists</a></span></li></ul></li> <li><span class="nowrap"><a href="/wiki/Zodiac" title="Zodiac">Zodiac</a></span></li></ul> 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