Within <a href="https://en.wikipedia.org/wiki/Ursa_Minor" id="mwATM" rel="mw:WikiLink" title="Ursa Minor">Ursa Minor</a>, <a href="https://en.wikipedia.org/wiki/H1504+65" id="mwATQ" rel="mw:WikiLink" title="H1504+65">H1504+65</a>, a <a href="https://en.wikipedia.org/wiki/White_dwarf" id="mwATU" rel="mw:WikiLink" title="White dwarf">white dwarf</a> with the hottest known surface temperature in the universe at 200,000 K, was documented.<sup about="#mwt113" class="mw-ref reference" data-mw='{"name":"ref","attrs":{},"body":{"id":"mw-reference-text-cite_note-21"}}' id="cite_ref-21" rel="dc:references" typeof="mw:Extension/ref"><a href="./January_27#cite_note-21" id="mwATY" style="counter-reset: mw-Ref 21;"><span class="mw-reflink-text" id="mwATc">[21]</span></a></sup>
<span class="mw-reference-text" id="mw-reference-text-cite_note-21"><cite about="#mwt110" class="citation journal cs1" id="CITEREFWernerRauch,_T.2011">Werner, K.; Rauch, T. (2011). "UV Spectroscopy of the Hot Bare Stellar Core H1504+65 with the HST Cosmic Origins Spectrograph". <i id="mwB68"><a href="./Astrophysics_and_Space_Science" id="mwB7A" rel="mw:WikiLink" title="Astrophysics and Space Science">Astrophysics and Space Science</a></i>. <b id="mwB7E">335</b> (1): 121–24. <a class="mw-redirect" href="./Bibcode_(identifier)" id="mwB7I" rel="mw:WikiLink" title="Bibcode (identifier)">Bibcode</a>:<a class="external text" href="https://ui.adsabs.harvard.edu/abs/2011Ap&amp;SS.335..121W" id="mwB7M" rel="mw:ExtLink nofollow">2011Ap<span id="mwB7Q" typeof="mw:Entity">&amp;</span>SS.335..121W</a>. <a class="mw-redirect" href="./Doi_(identifier)" id="mwB7U" rel="mw:WikiLink" title="Doi (identifier)">doi</a>:<a class="external text" href="https://doi.org/10.1007%2Fs10509-011-0617-x" id="mwB7Y" rel="mw:ExtLink nofollow">10.1007/s10509-011-0617-x</a>. <a class="mw-redirect" href="./S2CID_(identifier)" id="mwB7c" rel="mw:WikiLink" title="S2CID (identifier)">S2CID</a><span id="mwB7g" typeof="mw:Entity"> </span><a class="external text" href="https://api.semanticscholar.org/CorpusID:116910726" id="mwB7k" rel="mw:ExtLink nofollow">116910726</a>.</cite><span about="#mwt110" class="Z3988" id="mwB7o" title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=Astrophysics+and+Space+Science&amp;rft.atitle=UV+Spectroscopy+of+the+Hot+Bare+Stellar+Core+H1504%2B65+with+the+HST+Cosmic+Origins+Spectrograph&amp;rft.volume=335&amp;rft.issue=1&amp;rft.pages=121-24&amp;rft.date=2011&amp;rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A116910726%23id-name%3DS2CID&amp;rft_id=info%3Adoi%2F10.1007%2Fs10509-011-0617-x&amp;rft_id=info%3Abibcode%2F2011Ap%26SS.335..121W&amp;rft.aulast=Werner&amp;rft.aufirst=K.&amp;rft.au=Rauch%2C+T.&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AJanuary+27"></span></span>