Yes there is, actually. I won't get into the math or the overly verbose stuff, but to put it in a simple way: Since every planet revolves around our Sun in a certain orbital path, which thanks to technology has been measured for most objects in our solar system, astronomers can find patterns and determine where things were in the past.

For example, we all know the Earth takes 365 days to go around the Sun--that is our year. We could easily turn back the clocks thousands of years before astronomy ever existed to determine where the Earth was compared to the Sun, say in like 200BC. There are many computer programs for this nowadays.

This is why we now know where planets like Saturn and Pluto have historically been, since we can do the math around their orbital patterns. Since it takes Pluto around 250 years to travel one complete circle around the Sun, and since Zodiac signs exist, we can look at the sign & degree of where Pluto is right this very minute, and do the math to figure out the last time it was in that spot. It was indeed in the early days of our great country, from the revolutionary war through 1776, that Pluto was hanging out in late Capricorn/early Aquarius like it is right now~