Interactive Orbit: INTERACTIVE
C/2020 B3 (Rankin) has an eccentricity of 0.998 - making it near parabolic. Usually a parabolic comet doesn't have an orbital period defined. The shape of the orbit is not closed. The orbits can be extremely long, and often these comets are only making a single visit to the inner solar system.
C/2020 B3 (Rankin) looks to have an orbital period around 84,100 years.
The last time this comet passed near the inner solar system, human's had not yet discovered the Americas. Giant ice age beasts like mastodons, giant sloths, saber-toothed cats, and mammoths ruled. Modern civilization in any sense did not yet exist. People were nomadic hunter gatherers using stone tools to kill large game. Modern Homo Sapiens had not yet left Africa and spread across Europe. An infrequent visitor to say the least.
Stacked - coadd of discovery images inverted: