There are many events which happen just once and never repeat exactly, at least within a human life span. These phenomena include solar and lunar eclipses, planetary conjunctions, meteor showers etc.
:: 2015-03-17 Aurora ::
:: 2015-03-20 Partial Solar Eclipse ::
:: 2012-06-06 Transit of Venus (ToV) ::
:: 2011-01-11 - Moon and Jupiter conjunction over Warsaw ::
:: 2011-01-04 Partial Solar Eclipse ::
2008-08-01 Solar Eclipse
:: 2008-02-21 Total Lunar Eclipse ::
:: 2006 VV2 ::
:: 2007-03-03 Total Lunar Eclipse ::
:: 2006-06-08 Conjunction of the Moon and Jupiter ::
:: 2006-04-14 Moon and Jupiter conjunction and interesting halo ::