Birchas Hachama  -  Once every 28 years the sun arrives at the exact location where  it was created, at the moment it was created, and a special blessing is recited. This year (2009), that event occurs on Wednesday, April 8, Erev Pesach.  Rabbi Paltiel gives an introduction to the idea of Birchas Hachama in a shiur based on a sicha from Likutei Sichos Vol. 22 (pp. 201-202).

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