The Ursa Major Cycle ( Sapta Rishi Yuga )

The Ursa Major is a constellation called the Great Bear. They are known in Indian Astronomy as the Seven Seers or Sapta Rishies - Atri, Angiras, Mareechi, Pulasthya, Pulaha, Krithu, Vasishta.

They stay in a constellation for 100 years. Since the Sidereal Zodiac is made up of 27 constellations, they take 27*100 = 2700 years to make a circuit of the Zodiac. Their motion is retrograde.

Their wives are Pleiades, the Seven Sisters, known as Karthika !

Prof Drayson writes in " Asiatic Researches " " that the ancient Indians thought proper to connect their Mythology with an astronomical cycle of a strange nature. It is that of the Seven Rishies ( Ursa Major ), moving along the Zodiac in a retrograde motion of 2700 years."

So by tracking their movements Time can be calculated. In fact the first astronomical calender was erected by the Indian emperor, Vaivaswatha Manu in circa 3700 BC. It was based on the Ursa Major cycle.

The Ursa Major, Sapta Rishies, were in Regulus at the start of the Mahabharatha war.

Time can be measured, not only by Solar cycles or lunar cycles, but also by the Ursa Major Cycle.