One interesting theory,

what the vedas has written is true. But not in this planet, some other planet. The alien came to earth and gave people a way to live. Then the alien gave some interesting fact about their research and some of the inventions they already have in their planet. It is also possible that those alien taught some of these to the rishi munis and those somehow educated people wrote about those things in the book. Sanskrit may not be the language developed by indian. It may have been provided by alien.
Do not know but suddenly this thought came to my mind. If aliens are smart and much more advanced than us, definitely this is possible. They can travel in the speed of light. And to do that, they need to know the information about the atoms and stuffs. Then only they will be able to fly at this speed.
There is also highly possible that we human being do lots of research about new habitation and stuffs. Same way some aliens maybe researching on us.
Let me know if someone in Sajha has somewhat similar thinking.
Regards