Arundhati & Vasishtha through last 18,000 years.
For the most part (as is the case today and for last 6500 years or before 12,000 BCE) Vasishtha was walking ahead of Arundhati, however, Vyasa states that Arundhati was walking ahead of Vasishtha @ the time of Mahabharata War.
A wonderful astronomy simulation.
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