An interesting news feature appeared In Nature (26 July 2012) on a portable geochronometer developed by Scott Anderson of the Southwest Research Institute in Boulder, Colorado for speed dating rocks on moon and the mars using tunable laser and employing the Rb 87 /Sr 87 method.

MSR/16 Aug.2012

Source: Eric Hand (2012) – The Time Machine, Nature, v.487, pp.422-425.