Numerical absolute geologic age dating
Geochronology is the science of dating and determining the time sequence of events in the history of the Earth.This web page provides an overview of selected geochronology methods used by USGS scientists.However, we have to have actual samples of the surface material to figure out the absolute geologic age, which make it much harder to determine for extraterrestrial objects.
To fully understand the geology of body with a solid surface, such as a terrestrial planet or moon, planetary scientists need to know about the history of the surface.
Generally, the easiest thing to study is the relative geologic age.
These are often characterised as the norm, rather than the exception.
I thought it would be useful to present an example where the geology is simple, and unsurprisingly, the method does work well, to show the quality of data that would have to be invalidated before a major revision of the geologic time scale could be accepted by conventional scientists.
New dating methods are invented all the time, however, most have practical limitations.