<a href="https://en.wikipedia.org/wiki/Johann_Georg_Tralles" id="mwgg" rel="mw:WikiLink" title="Johann Georg Tralles">Johann Georg Tralles</a> discovers the <a href="https://en.wikipedia.org/wiki/Great_Comet_of_1819" id="mwgw" rel="mw:WikiLink" title="Great Comet of 1819">Great Comet of 1819</a>, (C/1819 N1). It is the first comet analyzed using <a href="https://en.wikipedia.org/wiki/Polarimetry" id="mwhA" rel="mw:WikiLink" title="Polarimetry">polarimetry</a>, by <a href="https://en.wikipedia.org/wiki/François_Arago" id="mwhQ" rel="mw:WikiLink" title="François Arago">François Arago</a>.