Micron Document
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</style><div id="coordinates" class="coordinates"><a class="external text" href="https://geohack.toolforge.org/skyhack.php?ra=15.578130555556&amp;de=26.714694444444&amp;size=0.016666666666667&amp;name=Gemma&amp;_globe:=">Datenbanklinks zu Gemma</a></div>
<table aria-label="Kenndaten des Doppelsterns" class="wikitable infobox float-right ibtable">

<tbody><tr>
<th colspan="3" class="ibheader">Doppelstern<br>α Coronae Borealis
</th></tr>
<tr>
<td colspan="3" class="ibimage notheme">
</td></tr>
<tr>
<td colspan="3" class="ibimgtxt notheme">Amateur-Astrofoto von α Coronae Borealis (Ausschnitt ca. 40′ × 30′).
</td></tr>
<tr style="display:none;">
<td colspan="3" class="ibmap notheme"><div style="position:relative;"><table style="border:0; width:330px; text-align:left; display:inline-table;"><tbody><tr><td style="border:0; padding:0;"><div style="position: relative;"><div style="position: absolute; display: block; padding:0px; margin:0px; left:0px; top:0px;"><span typeof="mw:File"></span></div><span typeof="mw:File"></span></div></td></tr></tbody></table><span style="display:none;">Vorlage:Skymap/Wartung/CrB</span></div>
</td></tr>
<tr>
<td colspan="3" class="ibmap notheme"><div class="notheme" style="position: relative; width: 330px; margin: auto; float: ; clear: ; background:#ffffff;"><div style="position: absolute; left: 200px; top: 156px; padding: 0;"><span class="mw-valign-top" typeof="mw:File"></span></div><span typeof="mw:File"></span></div>
</td></tr>
<tr style="display:none;">
<td colspan="3" class="ibmaptxt notheme">
</td></tr>
<tr>
<th colspan="3" class="ibheader">Beobachtungsdaten<br><small><a href="%C3%84quinoktium" title="Äquinoktium">Äquinoktium</a>:&nbsp;<a href="Epoche_(Astronomie)#Standardepochen" title="Epoche (Astronomie)">J2000.0</a>, <a href="Epoche_(Astronomie)" title="Epoche (Astronomie)">Epoche</a>:&nbsp;J2000.0</small>
</th></tr>
<tr>
<td colspan="3" style="text-align:center;"><a rel="nofollow" class="external text" href="https://aladin.cds.unistra.fr/AladinLite/?target=15%2034%2041.27%20%2B26%2042%2052.9&amp;fov=0.016666666666667&amp;survey=CDS%2FP%2FDSS2%2Fcolor">AladinLite</a>
</td></tr>
<tr>
<td><a href="Sternbild" title="Sternbild">Sternbild</a>
</td>
<td colspan="2" class="ibnowrap"><a href="N%C3%B6rdliche_Krone" title="Nördliche Krone">Nördliche Krone</a>
</td></tr>
<tr style="display:none;">
<td><a href="Rektaszension" title="Rektaszension">Rektaszension</a>
</td>
<td colspan="2" class="ibnowrap">15h&nbsp;34m&nbsp;41,27s<sup id="cite_ref-HIP2_1-0" class="reference"><a href="#cite_note-HIP2-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup>
</td></tr>
<tr style="display:none;">
<td><a href="Deklination_(Astronomie)" title="Deklination (Astronomie)">Deklination</a>
</td>
<td colspan="2" class="ibnowrap">+26°&nbsp;42′&nbsp;52,9″<sup id="cite_ref-HIP2_1-0" class="reference"><a href="#cite_note-HIP2-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup>
</td></tr>
<tr>
<td><a href="Scheinbare_Helligkeit" title="Scheinbare Helligkeit">Scheinbare&nbsp;Helligkeit</a>&nbsp;
</td>
<td colspan="2" class="ibnowrap">2,23<sup id="cite_ref-HR_2-0" class="reference"><a href="#cite_note-HR-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> (2,21 – 2,32)<sup id="cite_ref-GCVS_3-0" class="reference"><a href="#cite_note-GCVS-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup>&nbsp;mag
</td></tr>
<tr style="display:none;">
<td>Bekannte <a href="Exoplanet" title="Exoplanet">Exoplaneten</a>
</td>
<td colspan="2">
<p><br>
</p>
</td></tr>
<tr style="display:none;">
<td colspan="3" class="ibheader">Position des Begleiters
</td></tr>
<tr style="display:none;">
<td>Winkelabstand
</td>
<td colspan="2" class="ibnowrap">{{{Winkelabstand}}}
</td></tr>
<tr style="display:none;">
<td><a href="Positionswinkel" title="Positionswinkel">Positionswinkel</a>
</td>
<td colspan="2" class="ibnowrap">{{{Positionswinkel}}}
</td></tr>
<tr>
<th colspan="3" class="ibheader"><a href="Astrometrie" title="Astrometrie">Astrometrie</a>
</th></tr>
<tr>
<td><a href="Radialgeschwindigkeit" title="Radialgeschwindigkeit">Radialgeschwindigkeit</a>
</td>
<td colspan="2" class="ibnowrap">1,7 ± 0,9 km/s<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup>
</td></tr>
<tr>
<td><a href="Parallaxe" title="Parallaxe">Parallaxe</a>
</td>
<td colspan="2" class="ibnowrap">43,46 ± 0,28 <a href="Winkelsekunde" title="Winkelsekunde">mas</a><sup id="cite_ref-HIP2_1-1" class="reference"><a href="#cite_note-HIP2-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup>
</td></tr>
<tr>
<td>Entfernung&nbsp;<sup id="cite_ref-LJPC_5-0" class="reference"><a href="#cite_note-LJPC-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup>
</td>
<td colspan="2" class="ibnowrap">75,0 ± 0,5 <a href="Lichtjahr" title="Lichtjahr">Lj</a><br><small>(23,0 ± 0,15 <a href="Parsec" title="Parsec">pc</a>)</small>
</td></tr>
<tr style="display:none;">
<td><a href="Absolute_Helligkeit" title="Absolute Helligkeit">Absolute visuelle Helligkeit</a> M<sub>vis</sub>
</td>
<td colspan="2" class="ibnowrap">mag
</td></tr>
<tr style="display:none;">
<td><a href="Absolute_Helligkeit" title="Absolute Helligkeit">Absolute bolometrische Helligkeit</a> M<sub>bol</sub>
</td>
<td colspan="2" class="ibnowrap">mag
</td></tr>
<tr style="display:none;">
<td colspan="3" style="color:#ff0000;text-align:center;"><b>Veralteter Parameter "Absolut"&nbsp;!</b>
</td></tr>
<tr>
<th colspan="3" class="ibheader"><a href="Eigenbewegung_(Astronomie)" title="Eigenbewegung (Astronomie)">Eigenbewegung</a><sup id="cite_ref-HIP2_1-2" class="reference"><a href="#cite_note-HIP2-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup>
</th></tr>
<tr>
<td>Rektaszensionsanteil:
</td>
<td colspan="2" class="ibnowrap">120,27 ± 0,19 <a href="Winkelsekunde" title="Winkelsekunde">mas</a>/<a href="Jahr" title="Jahr">a</a>
</td></tr>
<tr>
<td>Deklinationsanteil:
</td>
<td colspan="2" class="ibnowrap">−89,58 ± 0,20 <a href="Winkelsekunde" title="Winkelsekunde">mas</a>/<a href="Jahr" title="Jahr">a</a>
</td></tr>
<tr>
<th colspan="3" class="ibheader">Orbit<sup id="cite_ref-Tom86_6-0" class="reference"><a href="#cite_note-Tom86-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup>
</th></tr>
<tr>
<td><a href="Umlaufzeit" title="Umlaufzeit">Periode</a>
</td>
<td colspan="2" class="ibnowrap">17,35990 <a href="Tag" title="Tag">d</a>
</td></tr>
<tr style="display:none;">
<td><a href="Halbachsen_der_Ellipse" title="Halbachsen der Ellipse">Große Halbachse</a>
</td>
<td colspan="2" class="ibnowrap">
</td></tr>
<tr style="display:none;">
<td><a href="Exzentrizit%C3%A4t_(Astronomie)" title="Exzentrizität (Astronomie)">Exzentrizität</a>
</td>
<td colspan="2" class="ibnowrap">
</td></tr>
<tr style="display:none;">
<td><a href="Apsis_(Astronomie)" title="Apsis (Astronomie)">Periastron</a>
</td>
<td colspan="2" class="ibnowrap">
</td></tr>
<tr style="display:none;">
<td><a href="Apsis_(Astronomie)" title="Apsis (Astronomie)">Apastron</a>
</td>
<td colspan="2" class="ibnowrap">
</td></tr>
<tr style="display:none;">
<td><a href="Bahnneigung" title="Bahnneigung">Bahnneigung</a>
</td>
<td colspan="2" class="ibnowrap">
</td></tr>
<tr style="display:none;">
<td><a href="Argument_des_Knotens" class="mw-redirect" title="Argument des Knotens">Argument des Knotens</a>
</td>
<td colspan="2" class="ibnowrap">
</td></tr>
<tr style="display:none;">
<td>Epoche des Periastrons
</td>
<td colspan="2" class="ibnowrap">
</td></tr>
<tr style="display:none;">
<td>Argument der Periapsis
</td>
<td colspan="2" class="ibnowrap">
</td></tr>
<tr>
<th colspan="3" class="ibheader">Einzeldaten
</th></tr>
<tr>
<td>Namen
</td>
<td colspan="2" style="white-space:nowrap;">A; B
</td></tr>









<tr>
<td colspan="3" class="ibheadercomp">Spektrum und Indices
</td></tr>
<tr>
<td rowspan="2" style="vertical-align:middle"><a href="Spektralklasse" title="Spektralklasse">Spektralklasse</a><sup id="cite_ref-Tom86_6-1" class="reference"><a href="#cite_note-Tom86-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup>
</td>
<td>A
</td>
<td style="white-space:nowrap;">A0 V
</td></tr>
<tr>
<td>B
</td>
<td style="white-space:nowrap;">G5 V
</td></tr>





<tr>
<td colspan="3" class="ibheadercomp">Physikalische Eigenschaften
</td></tr>




<tr>
<td rowspan="2" style="vertical-align:middle"><a href="Absolute_Helligkeit" title="Absolute Helligkeit">Absolute vis.<br>Helligkeit</a> M<sub>vis</sub><sup id="cite_ref-Tom86_6-2" class="reference"><a href="#cite_note-Tom86-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup>
</td>
<td>A
</td>
<td style="white-space:nowrap;">0,16 ± 0,20 mag
</td></tr>
<tr>
<td>B
</td>
<td style="white-space:nowrap;">5,05 ± 0,25 mag
</td></tr>


<tr>
<td rowspan="2" style="vertical-align:middle"><a href="Masse_(Physik)" title="Masse (Physik)">Masse</a><sup id="cite_ref-Tom86_6-3" class="reference"><a href="#cite_note-Tom86-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup>
</td>
<td>A
</td>
<td style="white-space:nowrap;">2,58 ± 0,045 <a href="Sonnenmasse" title="Sonnenmasse"><i>M</i><sub>☉</sub></a>
</td></tr>
<tr>
<td>B
</td>
<td style="white-space:nowrap;">0,92 ± 0,025 <a href="Sonnenmasse" title="Sonnenmasse"><i>M</i><sub>☉</sub></a>
</td></tr>
<tr>
<td rowspan="2" style="vertical-align:middle"><a href="Radius" title="Radius">Radius</a><sup id="cite_ref-Tom86_6-4" class="reference"><a href="#cite_note-Tom86-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup>
</td>
<td>A
</td>
<td style="white-space:nowrap;">3,04 ± 0,30 <a href="Sonnenradius" title="Sonnenradius"><i>R</i><sub>☉</sub></a>
</td></tr>
<tr>
<td>B
</td>
<td style="white-space:nowrap;">0,90 ± 0,04 <a href="Sonnenradius" title="Sonnenradius"><i>R</i><sub>☉</sub></a>
</td></tr>
<tr>
<td rowspan="2" style="vertical-align:middle"><a href="Leuchtkraft" title="Leuchtkraft">Leuchtkraft</a><sup id="cite_ref-Tom86_6-5" class="reference"><a href="#cite_note-Tom86-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup>
</td>
<td>A
</td>
<td style="white-space:nowrap;">~ 74 <a href="Leuchtkraft" title="Leuchtkraft"><i>L</i><sub>☉</sub></a>
</td></tr>
<tr>
<td>B
</td>
<td style="white-space:nowrap;">~ 0,8 <a href="Leuchtkraft" title="Leuchtkraft"><i>L</i><sub>☉</sub></a>
</td></tr>
<tr>
<td rowspan="2" style="vertical-align:middle"><a href="Effektive_Temperatur" title="Effektive Temperatur">Effektive Temperatur</a><sup id="cite_ref-Tom86_6-6" class="reference"><a href="#cite_note-Tom86-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup>
</td>
<td>A
</td>
<td style="white-space:nowrap;">9700 ± 200 <a href="Kelvin" title="Kelvin">K</a>
</td></tr>
<tr>
<td>B
</td>
<td style="white-space:nowrap;">5800 ± 300 <a href="Kelvin" title="Kelvin">K</a>
</td></tr>




<tr>
<td>Alter
</td>
<td colspan="2" style="white-space:nowrap;">400 Millionen <a href="Jahr" title="Jahr">a</a><sup id="cite_ref-Sch_7-0" class="reference"><a href="#cite_note-Sch-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup>
</td></tr>


<tr>
<th colspan="3" class="ibheader">Andere Bezeichnungen und <a href="Liste_astronomischer_Kataloge" title="Liste astronomischer Kataloge">Katalogeinträge</a>
</th></tr>
<tr>
<td colspan="3" style="padding:0;"><table class="wikitable" style="box-sizing:border-box; width:100%; font-size:smaller; margin:0; border-collapse:collapse;"><tbody><tr><th style="white-space:nowrap;">Katalog</th><th>A</th><th>B</th></tr><tr><td style="white-space:nowrap;"><a href="Bayer-Bezeichnung" title="Bayer-Bezeichnung">Bayer-Bezeichnung</a></td><td colspan="2" style="white-space:nowrap;">α Coronae Borealis</td></tr><tr><td style="white-space:nowrap;"><a href="Flamsteed-Bezeichnung" title="Flamsteed-Bezeichnung">Flamsteed-Bezeichnung</a></td><td colspan="2" style="white-space:nowrap;">5 Coronae Borealis</td></tr><tr><td style="white-space:nowrap;"><a href="Bonner_Durchmusterung" title="Bonner Durchmusterung">Bonner Durchmusterung</a></td><td colspan="2" style="white-space:nowrap;"> BD +27° 2512</td></tr><tr><td style="white-space:nowrap;"><a href="Sternkatalog#Gliese_(Gl)_und_Gliese-Jahreiß_(GJ)" title="Sternkatalog">Gliese-Katalog</a></td><td colspan="2" style="white-space:nowrap;"> GJ 9524 <a rel="nofollow" class="external autonumber" href="https://vizier.u-strasbg.fr/viz-bin/VizieR-S?GJ%209524">[1]</a></td></tr><tr><td style="white-space:nowrap;"><a href="Bright-Star-Katalog" title="Bright-Star-Katalog">Bright-Star-Katalog</a></td><td colspan="2" style="white-space:nowrap;">HR 5793 <a rel="nofollow" class="external autonumber" href="https://cdsarc.u-strasbg.fr/viz-bin/VizieR-5?-source=V/50&amp;-out.all&amp;-out.max=10&amp;HR==5793">[2]</a></td></tr><tr><td style="white-space:nowrap;"><a href="Henry-Draper-Katalog" title="Henry-Draper-Katalog">Henry-Draper-Katalog</a></td><td colspan="2" style="white-space:nowrap;">HD 139006 <a rel="nofollow" class="external autonumber" href="https://cdsarc.u-strasbg.fr/viz-bin/VizieR-5?-source=III/135A/catalog&amp;-out.all&amp;-out.max=10&amp;HD==139006">[3]</a></td></tr><tr><td style="white-space:nowrap;"><a href="SAO-Katalog" title="SAO-Katalog">SAO-Katalog</a></td><td colspan="2" style="white-space:nowrap;">SAO 83893 <a rel="nofollow" class="external autonumber" href="https://cdsarc.u-strasbg.fr/viz-bin/VizieR-5?-source=I/131A/sao&amp;-out.all&amp;-out.max=10&amp;SAO==83893">[4]</a></td></tr><tr><td style="white-space:nowrap;"><a href="Tycho-1-Katalog" title="Tycho-1-Katalog">Tycho-Katalog</a></td><td colspan="2" style="white-space:nowrap;">TYC 2029-1690-1<a rel="nofollow" class="external autonumber" href="https://cdsarc.u-strasbg.fr/viz-bin/VizieR-5?-source=I/259&amp;-out.all&amp;-out.max=100&amp;TYC1=2029&amp;TYC2=1690&amp;TYC3=1">[5]</a></td></tr><tr><td style="white-space:nowrap;"><a href="Hipparcos-Katalog" title="Hipparcos-Katalog">Hipparcos-Katalog</a></td><td colspan="2" style="white-space:nowrap;">HIP 76267 <a rel="nofollow" class="external autonumber" href="https://vizier.u-strasbg.fr/viz-bin/VizieR-5?-source=I/311&amp;-out.all&amp;-out.max=10&amp;HIP==76267">[6]</a></td></tr><tr><td style="white-space:nowrap;">Weitere Bezeichnungen:</td><td colspan="2">
<a href="FK5" title="FK5">FK5</a> 578</td>
</tr></tbody></table>
</td></tr>

</tbody></table><p><span style="display:none">Vorlage:Infobox Doppelstern/Wartung/RekDekSizeLeer</span>
</p><p><b>α Coronae Borealis</b> (<i>Alpha Coronae Borealis</i>, kurz <i>α CrB</i>) ist der hellste <a href="Stern" title="Stern">Stern</a> im <a href="Sternbild" title="Sternbild">Sternbild</a> <a href="N%C3%B6rdliche_Krone" title="Nördliche Krone">Nördliche Krone</a>. Es handelt sich um einen <a href="Spektroskopischer_Doppelstern" title="Spektroskopischer Doppelstern">spektroskopischen Doppelstern</a> sowie <a href="Bedeckungsver%C3%A4nderlicher_Stern" title="Bedeckungsveränderlicher Stern">bedeckungsveränderlichen Stern</a> vom <a href="Algolstern" title="Algolstern">Typ Algol</a>. α Coronae Borealis ist auch unter den Namen <b>Gemma</b> (lateinisch „Edelstein“) und <b>Alphekka</b> (<i>Alphecca</i>, aus dem Arabischen) bekannt.
</p>

<div class="mw-heading mw-heading2"><h2 id="Namen">Namen</h2></div>
<p><i>Gemma</i> ist lateinisch für „Edelstein“, was bereits auf die Kronengestalt des Sternbildes anspielt. Der Name Gemma für den Stern wurde aber in der Antike nicht verwendet, sondern erst später eingeführt. In <a href="Vergil" title="Vergil">Vergils</a> <i><a href="Georgica" title="Georgica">Georgica</a></i> wird der Stern als <i>Gnosia Stella Coronae</i> (lateinisch „Stern der Krone <a href="Knossos" title="Knossos">Knossos</a>’“) erwähnt. Der aus dem Arabischen stammende Name <i>Alphekka</i> (<i>Alphecca</i>) leitet sich von <a href="Ulugh_Beg" title="Ulugh Beg">Ulugh Begs</a> <i>Al Nāʽir al Fakkah</i> ab, was so viel wie „der Helle [Stern] der Schale“ bedeutet.<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> Die <a href="Internationale_Astronomische_Union" title="Internationale Astronomische Union">Internationale Astronomische Union</a> hat am 20. Juli 2016 den Eigennamen <i>Alphecca</i> als standardisierten Eigennamen festgelegt.<sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup>
</p><p><span id="Balre.C5.A1a"></span><span id="Balreša"></span><i>Balreša</i> (<sup>MUL</sup>Balreša) war die <a href="Mesopotamien" title="Mesopotamien">mesopotamische</a> Bezeichnung des Sterns. α Coronae Borealis galt als Stern der Göttin <a href="Nanaja" title="Nanaja">Nanaja</a>. Balreša folgte als <i>Stern des <a href="Enlil" title="Enlil">Enlil</a></i> der Gottheit <sup><a href="Dingir" title="Dingir">d</a></sup>Bizilla. Beide gehörten zu der Gruppe der <i>Enlil-Sterne</i>. Nanaja zählte dabei als Balreša zu den sechs <i>himmlischen Palastfrauen</i>.<sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup>
</p>
<div class="mw-heading mw-heading2"><h2 id="Eigenschaften">Eigenschaften</h2></div>
<p>α Coronae Borealis liegt 23 <a href="Parsec" title="Parsec">Parsec</a> (75 Lichtjahre) von der Sonne entfernt.<sup id="cite_ref-LJPC_5-1" class="reference"><a href="#cite_note-LJPC-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> <a href="Johannes_Franz_Hartmann" title="Johannes Franz Hartmann">Johannes Franz Hartmann</a> stellte 1902/03 fest, dass α Coronae Borealis ein spektroskopischer Doppelstern ist. Eine Bahn wurde erstmals 1909 von Frank Craig Jordan berechnet.<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> <a href="Joel_Stebbins" title="Joel Stebbins">Joel Stebbins</a> entdeckte die Veränderlichkeit des Sterns (1914).<sup id="cite_ref-Tom86_6-7" class="reference"><a href="#cite_note-Tom86-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> Bei α Coronae Borealis handelt es sich um einen <a href="Algolstern" title="Algolstern">Algolstern</a>; die Helligkeit schwankt mit einer Periode von 17,36 Tagen (zugleich die Umlaufzeit des Doppelsternsystems) zwischen 2,2 mag und 2,3 mag.<sup id="cite_ref-GCVS_3-1" class="reference"><a href="#cite_note-GCVS-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> Der Hauptstern des Systems ist ein <a href="Hauptreihenstern" class="mw-redirect" title="Hauptreihenstern">Hauptreihenstern</a> vom <a href="Spektraltyp" class="mw-redirect" title="Spektraltyp">Spektraltyp</a> A0. Er besitzt eine Masse von 2,6 Sonnenmassen, einen Radius von 3,0 Sonnenradien und die rund 70-fache Leuchtkraft der Sonne. Der Begleiter ist ein Hauptreihenstern vom Spektraltyp G5 mit 0,9 Sonnenmassen.<sup id="cite_ref-Tom86_6-8" class="reference"><a href="#cite_note-Tom86-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup>
</p><p>Mit Hilfe von modernen präzisen Messungen sowie der mittlerweile über ein Jahrhundert zurückreichenden Beobachtungsdaten konnte auch eine <a href="Apsidendrehung" title="Apsidendrehung">Apsidendrehung</a> nachgewiesen werden. Es wurde berechnet, dass die Apsidenlinie für eine Drehung 6600 bis 10&nbsp;600 Jahre benötigt.<sup id="cite_ref-Sch_7-1" class="reference"><a href="#cite_note-Sch-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup>
</p><p>Die Bewegung durch den Raum lässt annehmen, dass α Coronae Borealis dem <a href="Ursa-Major-Strom" class="mw-redirect" title="Ursa-Major-Strom">Ursa-Major-Strom</a> (Bärenstrom) angehört, einem am Himmel weit verstreuten <a href="Bewegungshaufen" title="Bewegungshaufen">Bewegungshaufen</a>.<sup id="cite_ref-Kin03_12-0" class="reference"><a href="#cite_note-Kin03-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup>
</p>
<div class="mw-heading mw-heading2"><h2 id="Siehe_auch">Siehe auch</h2></div>
<ul><li><a href="Liste_der_hellsten_Sterne" title="Liste der hellsten Sterne">Liste der hellsten Sterne</a></li></ul>
<div class="mw-heading mw-heading2"><h2 id="Weblinks">Weblinks</h2></div>
<ul><li><a rel="nofollow" class="external free" href="http://stars.astro.illinois.edu/Sow/alphecca.html">http://stars.astro.illinois.edu/Sow/alphecca.html</a></li>
<li><a rel="nofollow" class="external text" href="https://simbad.u-strasbg.fr/simbad/sim-id?Ident=alf+CrB">SIMBAD-Datenbankeintrag.</a></li></ul>
<div class="mw-heading mw-heading2"><h2 id="Einzelnachweise">Einzelnachweise</h2></div>
<ol class="references">
<li id="cite_note-HIP2-1"><span class="mw-cite-backlink">↑ <sup><a href="#cite_ref-HIP2_1-0">a</a></sup> <sup><a href="#cite_ref-HIP2_1-1">b</a></sup> <sup><a href="#cite_ref-HIP2_1-2">c</a></sup></span> <span class="reference-text">Floor van Leeuwen: <i><a href="Hipparcos-Katalog" title="Hipparcos-Katalog">Hipparcos, the New Reduction</a></i>. <a href="VizieR" title="VizieR">VizieR</a>-Datenkatalog I/311 (elektronisch veröffentlicht). 2008, <a href="Bibcode" title="Bibcode">bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2008yCat.1311....0V">2008yCat.1311....0V</a>. <a rel="nofollow" class="external text" href="https://vizier.cds.unistra.fr/viz-bin/VizieR-5?-source=I/311/hip2&amp;HIP=76267">VizieR-Katalogeintrag</a>.</span>
</li>
<li id="cite_note-HR-2"><span class="mw-cite-backlink"><a href="#cite_ref-HR_2-0">↑</a></span> <span class="reference-text">Dorrit Hoffleit, Wayne H. Warren, Jr.: <i><a href="Bright-Star-Katalog" title="Bright-Star-Katalog">Bright Star Catalogue, 5th Revised Ed.</a></i> <a href="VizieR" title="VizieR">VizieR</a>-Datenkatalog V/50 (elektronisch veröffentlicht). 1995, <a href="Bibcode" title="Bibcode">bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1995yCat.5050....0H">1995yCat.5050....0H</a>. <a rel="nofollow" class="external text" href="https://vizier.cds.unistra.fr/viz-bin/VizieR-5?-source=V/50&amp;HR=5793">VizieR-Katalogeintrag</a>. </span>
</li>
<li id="cite_note-GCVS-3"><span class="mw-cite-backlink">↑ <sup><a href="#cite_ref-GCVS_3-0">a</a></sup> <sup><a href="#cite_ref-GCVS_3-1">b</a></sup></span> <span class="reference-text">Nikolay N. Samus et al.: <i>General Catalogue of Variable Stars</i>. Vers. 5.1, März 2017. <a href="VizieR" title="VizieR">VizieR</a>-Datenkatalog B/gcvs (elektronisch veröffentlicht). 2009, <a href="Bibcode" title="Bibcode">bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2009yCat....102025S">2009yCat....102025S</a>. <a rel="nofollow" class="external text" href="https://vizier.cds.unistra.fr/viz-bin/VizieR-5?-source=B/gcvs/gcvs_cat&amp;GCVS=alf%20CrB">VizieR-Katalogeintrag</a>.</span>
</li>
<li id="cite_note-4"><span class="mw-cite-backlink"><a href="#cite_ref-4">↑</a></span> <span class="reference-text">Ralph Elmer Wilson: <i>General Catalogue of Stellar Radial Velocities</i>. <a href="VizieR" title="VizieR">VizieR</a>-Datenkatalog III/21 (elektronisch veröffentlicht). 1953/2010, <a href="Bibcode" title="Bibcode">bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2010yCat.3021....0W">2010yCat.3021....0W</a>. <a rel="nofollow" class="external text" href="https://vizier.cds.unistra.fr/viz-bin/VizieR-5?-source=III/21/gcrv&amp;GCRV=8990">VizieR-Katalogeintrag</a>.</span>
</li>
<li id="cite_note-LJPC-5"><span class="mw-cite-backlink">↑ <sup><a href="#cite_ref-LJPC_5-0">a</a></sup> <sup><a href="#cite_ref-LJPC_5-1">b</a></sup></span> <span class="reference-text">Von der Parallaxe abgeleitet (43,46 ± 0,28 mas, <a href="Hipparcos-Katalog" title="Hipparcos-Katalog">Hipparcos, the New Reduction</a>).</span>
</li>
<li id="cite_note-Tom86-6"><span class="mw-cite-backlink">↑ <sup><a href="#cite_ref-Tom86_6-0">a</a></sup> <sup><a href="#cite_ref-Tom86_6-1">b</a></sup> <sup><a href="#cite_ref-Tom86_6-2">c</a></sup> <sup><a href="#cite_ref-Tom86_6-3">d</a></sup> <sup><a href="#cite_ref-Tom86_6-4">e</a></sup> <sup><a href="#cite_ref-Tom86_6-5">f</a></sup> <sup><a href="#cite_ref-Tom86_6-6">g</a></sup> <sup><a href="#cite_ref-Tom86_6-7">h</a></sup> <sup><a href="#cite_ref-Tom86_6-8">i</a></sup></span> <span class="reference-text">Jocelyn Tomkin, Daniel M. Popper: <i>Rediscussion of eclipsing binarties. XV. Alpha Coronae Borealis, a main-sequence system with components of types A and G</i>. In: <i><a href="The_Astronomical_Journal" class="mw-redirect" title="The Astronomical Journal">The Astronomical Journal</a></i>. Bd. 91, 1986, S. 1428–1437, <a href="Bibcode" title="Bibcode">bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1986AJ.....91.1428T">1986AJ.....91.1428T</a>, <a href="https://doi.org/10.1086/114121" class="extiw external" title="doi:10.1086/114121">doi:10.1086/114121</a>. </span>
</li>
<li id="cite_note-Sch-7"><span class="mw-cite-backlink">↑ <sup><a href="#cite_ref-Sch_7-0">a</a></sup> <sup><a href="#cite_ref-Sch_7-1">b</a></sup></span> <span class="reference-text">Jürgen H. M. M. Schmitt et al.: <i>The α CrB binary system: A new radial velocity curve, apsidal motion, and the alignment of rotation and orbit axes</i>. In: <i><a href="Astronomy_%26_Astrophysics" title="Astronomy &amp; Astrophysics">Astronomy &amp; Astrophysics</a></i>. Bd. 586, 2016, Artikel-ID A104, <a href="Bibcode" title="Bibcode">bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2016A&amp;A...586A.104S">2016A&amp;A...586A.104S</a>, <a href="https://doi.org/10.1051/0004-6361/201526662" class="extiw external" title="doi:10.1051/0004-6361/201526662">doi:10.1051/0004-6361/201526662</a>.</span>
</li>
<li id="cite_note-8"><span class="mw-cite-backlink"><a href="#cite_ref-8">↑</a></span> <span class="reference-text">Richard Hinckley Allen: <i>Star-Names and their Meanings</i>. G. E. Stechert, New York 1899, S. 178–179. <a rel="nofollow" class="external text" href="https://penelope.uchicago.edu/Thayer/E/Gazetteer/Topics/astronomy/_Texts/secondary/ALLSTA/Corona_Borealis*.html">Transkription.</a></span>
</li>
<li id="cite_note-9"><span class="mw-cite-backlink"><a href="#cite_ref-9">↑</a></span> <span class="reference-text"><span class="cite"><a rel="nofollow" class="external text" href="http://www.pas.rochester.edu/~emamajek/WGSN/WGSN_bulletin1.pdf"><i>Bulletin of the IAU Working Group on Star Names, No. 1, July 2016.</i></a> (PDF)<span class="Abrufdatum"> Abgerufen am 9.&nbsp;November 2016</span> (englisch, 184 KiB).</span><span style="display: none;" class="Z3988" title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&amp;rfr_id=info%3Asid%2Fde.wikipedia.org%3AGemma&amp;rft.title=Bulletin+of+the+IAU+Working+Group+on+Star+Names%2C+No.+1%2C+July+2016&amp;rft.description=Bulletin+of+the+IAU+Working+Group+on+Star+Names%2C+No.+1%2C+July+2016&amp;rft.identifier=http%3A%2F%2Fwww.pas.rochester.edu%2F%7Eemamajek%2FWGSN%2FWGSN_bulletin1.pdf&amp;rft.language=en">&nbsp;</span></span>
</li>
<li id="cite_note-10"><span class="mw-cite-backlink"><a href="#cite_ref-10">↑</a></span> <span class="reference-text"><a href="Dietz-Otto_Edzard" class="mw-redirect" title="Dietz-Otto Edzard">Dietz-Otto Edzard</a>: <i><a href="Reallexikon_der_Assyriologie_und_vorderasiatischen_Arch%C3%A4ologie" class="mw-redirect" title="Reallexikon der Assyriologie und vorderasiatischen Archäologie">Reallexikon der Assyriologie und vorderasiatischen Archäologie</a></i>. Bd. 9, de Gruyter, Berlin 2001, ISBN 3-11-017296-8, S.&nbsp;147.</span>
</li>
<li id="cite_note-11"><span class="mw-cite-backlink"><a href="#cite_ref-11">↑</a></span> <span class="reference-text">Frank Craig Jordan: <i>The orbit of α Coronæ Borealis</i>. In: <i>Publications of the Allegheny Observatory of the University of Pittsburgh</i>. Bd. 1 (12), 1910, S. 85–91, <a href="Bibcode" title="Bibcode">bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1910PAllO...1...85J">1910PAllO...1...85J</a>.</span>
</li>
<li id="cite_note-Kin03-12"><span class="mw-cite-backlink"><a href="#cite_ref-Kin03_12-0">↑</a></span> <span class="reference-text">Jeremy R. King et al.: <i>Stellar Kinematic Groups. II. A Reexamination of the Membership, Activity, and Age of the Ursa Major Group</i>. In: <i><a href="The_Astronomical_Journal" class="mw-redirect" title="The Astronomical Journal">The Astronomical Journal</a></i>. Bd. 125 (4), 2002, S. 1980–2017, <a href="Bibcode" title="Bibcode">bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2003AJ....125.1980K">2003AJ....125.1980K</a>, <a href="https://doi.org/10.1086/368241" class="extiw external" title="doi:10.1086/368241">doi:10.1086/368241</a>.</span>
</li>
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