What is the reason for chanting Gayathri Mantra during santhyavanthanam?

According to our vedas, a brahmin should chant gayathri mantra 108 times daily in the morning. What happens in our body while chanting it. Why we need to chant 108 times specifically. Why we need to chant it by facing the sun early morning and why we should use water while chanting it.

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Why there is a custom to see the Arundathi star during the wedding?

Actually in our hindu tradition, it is a must that the husband and wife should see the Arundathi nakshatra during their wedding.

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