The following verses from the ADI PARVA of the Mahabharatha closely resembles the Big Bang theory. "And what is seen in the universe, whether animate or inanimate, of created things, will at the end of the world, and after the expiration of the Yuga, be again confounded. And, at the commencement of other Yugas, all things will be renovated, and, like the various fruits of the earth, succeed each other in the due order of their seasons. Thus continueth perpetually to revolve in the world, without beginning and without end, this wheel which causeth the destruction of all things"
In another instant ved vyas in a dialogue between Indra and Skanda states that [VANA PARVA 230 VERSES 8-11 ]

Contesting against Abhijit (Vega), the constellation Krittika (Pliedes) went to "Vana" the Summer Solstice to heat the summer. Then the star Abhijit slipped down in the sky. At that time Dhanishta was given the first place in the list of Nakshatras. Rohini was also the first some time back. Now you decide what to do," said Indra. 

This dialogue shows that when Indra went to Summer Solstice, Vega started falling down. Many scholards have ridiculed this idea of Star Falling; but now it is proved by modern astronomy that it was a true fact that 12,000 years B.C., Vega had really come down to the horizon from the heights of the sky, to become a pole star.

Krittikas were at the Summer Solstice between 21,800 and 20,840 years B.C. At this time Dhansishta was at the vernal equinox and hence was given the first place in the Nakshatras. From this period, the sages noticed the gradual fall of Abhijit. Falling steadily, it is assumed the position of the Celestial Pole at 12,000 B.C., when Indra met Skanda to think on the problem of time-reckoning. The story shows that the Indian sages were observing the stars and constellations at least from 23,000 years B.C.

References : The Summaries of papers read in The Seminar on the Mahabharat War, May 30-31, 1992. [source]