The <a href="https://en.wikipedia.org/wiki/Eris_(dwarf_planet)" id="mwASQ" rel="mw:WikiLink" title="Eris (dwarf planet)">dwarf planet Eris</a> is discovered by <a href="https://en.wikipedia.org/wiki/Palomar_Observatory" id="mwASU" rel="mw:WikiLink" title="Palomar Observatory">Palomar Observatory</a>-based astronomers, later motivating the <a href="https://en.wikipedia.org/wiki/International_Astronomical_Union" id="mwASY" rel="mw:WikiLink" title="International Astronomical Union">International Astronomical Union</a> (IAU) to <a href="https://en.wikipedia.org/wiki/Definition_of_planet" id="mwASc" rel="mw:WikiLink" title="Definition of planet">define the term <i id="mwASg">planet</i></a> for the first time.<sup about="#mwt192" class="mw-ref reference" data-mw='{"name":"ref","attrs":{"name":"New Planet"},"body":{"id":"mw-reference-text-cite_note-New_Planet-36"}}' id="cite_ref-New_Planet_36-0" rel="dc:references" typeof="mw:Extension/ref"><a href="./January_5#cite_note-New_Planet-36" id="mwASk" style="counter-reset: mw-Ref 36;"><span class="mw-reflink-text" id="mwASo">[36]</span></a></sup>