Until recently, rock art was largely ignored by archaeologists because there was no means for accurately placing them into the temporal record for association with other material remains at a site. The method we recently developed allows such small samples to be dated that determining the age of an ancient pictograph is now feasible. Pictograph samples from all over the world are being dated. 244Pu which fissions into 131-136Xe and 129I which decays into 129Xe.
Meteorites offer the oldest known material in our solar system.
Measurement of the noble gases permits us to determine the age of meteorites, the time when the elements were formed and the length of time the meteorite spent in space as a meter-sized body.