This scientific book should be done very carefully, so that people in general may not be mislead by the over intelligent scientists. There are so many contradictory things, but we have our authority and they have their authority. Our knowledge is from vedic scriptures which we accept as definite and without any mistake. A modern scientist believes that there was no civilization before 3,000 years, our Bhagavatam was spoken by Sukadeva Goswami 5,000 years ago and he is explaining "as I have heard it from authority", so we have got parampara system for millions of years. If there was no civilization before 3,000 years, then how this subject matter of knowledge could be discussed? How could it be received through the param-para system? So there is contradiction certainly. But the statement that there was no civilization 3,000 years ago can be adjusted by the conviction that there was civilization, millions and millions of years ago.
For more information regarding vedic astronomy you can consult any learned astronomer, there are many in Calcutta, my Guru Maharaja was also very learned in this field.