ancient jewish and chinese and other calendars also were devised to track these things... modern technology allows us to also further monitor the sunspots, plasma channels and explosions that blast plasma at us, and shower us with X-rays and other things, these all have massive influences, and the Hindus and their Yuga thing... yes, turns out that this is a cycle that is created by the rotation of the galactic disc and when it gets to the vertical points every ~12000 years it can cause such drastic effects as causing the entire earth to rotate to a new rotation axis, the 6000 and 12000 and 25000 year cycles the hindus talked about are real, and we are in the midst of a reversal now, and likely within 30 years there could be such a dramatic disaster that very few of us survive

according to fossil and genetic records, one of these transitions some 50,000 years ago almost wiped out humans altogether 

 in 30 years!  I'll stop saving for retirement then. 

 no, keep saving, but think about how to get into a place where you won't get washed away by the ocean flooding everything and the rain dumping petatons of water on you at the same time

also, pray that there is a Jesus and he's coming with his posse to collect the righteous 

 oh wait, so is 2nd coming something that also happens every 12,000 years? and they just take the lucky ones somewhere safe until it's all over and the cycle repeats? 

 The Hopi nation from the 4 corners region (Utah/Arizona, NM, Colorado) have the legend that they emerged from a cave in the ground and the god told them to spread out. 

 yes, "a god" in old myths is a keyword that usually refers to a human with advanced scientific knowledge and benevolent intentions, usually... some of them are not benevolent, thus shit like the human sacrifice of the aztecs and the more modern cult of kings 

 The dramatic disaster you describe seems terrifying. I’m still a believer of a positive change for humanity…. Even if this could be one… at least my descendants should live in paradise. 
The cosmic energies are so fascinating.