<a href="https://en.wikipedia.org/wiki/Alvan_Graham_Clark" id="mwXA" rel="mw:WikiLink" title="Alvan Graham Clark">Alvan Graham Clark</a> discovers the <a href="https://en.wikipedia.org/wiki/White_dwarf" id="mwXQ" rel="mw:WikiLink" title="White dwarf">white dwarf</a> star Sirius B, a companion of <a href="https://en.wikipedia.org/wiki/Sirius" id="mwXg" rel="mw:WikiLink" title="Sirius">Sirius</a>, through an <span about="#mwt41" data-mw='{"parts":[{"template":{"target":{"wt":"convert","href":"./Template:Convert"},"params":{"1":{"wt":"18.5"},"2":{"wt":"in"},"3":{"wt":"cm"},"adj":{"wt":"on"}},"i":0}}]}' id="mwXw" typeof="mw:Transclusion">18.5-inch (47</span><span about="#mwt41" typeof="mw:Entity"> </span><span about="#mwt41">cm)</span> telescope now located at <a href="https://en.wikipedia.org/wiki/Northwestern_University" id="mwYA" rel="mw:WikiLink" title="Northwestern University">Northwestern University</a>.<sup about="#mwt45" class="mw-ref reference" data-mw='{"name":"ref","attrs":{},"body":{"id":"mw-reference-text-cite_note-7"}}' id="cite_ref-7" rel="dc:references" typeof="mw:Extension/ref"><a href="./January_31#cite_note-7" id="mwYQ" style="counter-reset: mw-Ref 7;"><span class="mw-reflink-text" id="mwYg">[7]</span></a></sup>
<span class="mw-reference-text" id="mw-reference-text-cite_note-7"><cite about="#mwt42" class="citation book cs1" id="CITEREFSchilling2011">Schilling, Govert (2011). <a class="external text" href="https://books.google.com/books?id=e6OXczLD_tkC" id="mwBuk" rel="mw:ExtLink nofollow"><i id="mwBuo">Atlas of Astronomical Discoveries</i></a>. New York: Springer. p.<span id="mwBus" typeof="mw:Entity"> </span>71. <a class="mw-redirect" href="./ISBN_(identifier)" id="mwBuw" rel="mw:WikiLink" title="ISBN (identifier)">ISBN</a><span id="mwBu0" typeof="mw:Entity"> </span><a href="./Special:BookSources/9781441978103" id="mwBu4" rel="mw:WikiLink" title="Special:BookSources/9781441978103"><bdi id="mwBu8">9781441978103</bdi></a>.</cite><span about="#mwt42" class="Z3988" id="mwBvA" title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Atlas+of+Astronomical+Discoveries&amp;rft.place=New+York&amp;rft.pages=71&amp;rft.pub=Springer&amp;rft.date=2011&amp;rft.isbn=9781441978103&amp;rft.aulast=Schilling&amp;rft.aufirst=Govert&amp;rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3De6OXczLD_tkC&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AJanuary+31"></span></span>