Universe has many constellations.
The Big Dipper constellation is also called as Saptarshi.
Actually we should be proud of our Hindu Scriptures, as we our texts tell a lot about universe even before it was discovered by our scientists.
The list of the Seven Rishis is given by Jaiminiya Brahmana 2.218-221:
They are, Namely, :
Vasistha,
Bharadvaja,
Jamadagni,
Gautama,
Atri,
Visvamitra,
and Agastya,
The Saptarishis (seven sages) are the seven mind born sons of Brahma. They live for a period of time known as a manvantar (306,720,000 Earth Years). During this period of time they serve as representatives of Brahma.
Saptarishis occupy a position higher than that of all other devtas.
At the end of a manvantara the universe gets destroyed and Saptarishis merge in God the task of filling the earth is given to new appointed Saptarishis. And the cycle continues. ( In my future articles I will write about the age of Brahma also :)
Stay Tuned !