彗星 41p 改變旋轉方向
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41p
http://www.aerith.net/comet/catalog/0041P/2017.html
2017 list
http://familystar.org.tw/index.php?option=com_smf&Itemid=45&topic=24999.0==
http://www.skyandtelescope.com/observing/worldwide-4p-comet-campaign-needs-your-photos/
Comet 41P/Tuttle-Giacobini-Kresak begins the year moving north along the Leo-Cancer border, where it's well-placed for viewing in the evening sky. Watch for the comet to brighten from about magnitude +12 in mid-January to +10 by early March. Click for a full-size, printable finder chart.
Sky & Telescope diagram

Comet 41P/T-G-K passes closest to Earth (0.14 AU) in late March,