NWA 6255 meteorite − Thermophysical properties of interior and the crust

Differences in the thermophysical properties of NWA 6255 meteorite samples obtained from various locations with respect o the distance from the surface of the meteorite were evaluated by a differential scanning calorimetry (DSC). DSC is a perfect tool to experimentally verify theoretically predicted thermophysical properties of extraterrestrial matter. The specific heat capacity of the crust and the interior of meteorite were determined to be in the temperature range of 223‒823 K. Measured Cp values at room temperature for crust and for the interior of this meteorite were 602 and 668 J·kg–1·K–1, respectively. In addition, the phase transition of troilite from: (a) the fusion crust samples, (b) the edge part of the meteorite (1‒2 mm below the crust), and (c) the interior (over 10 mm below the fusion crust) was examined. It is shown that the shift of α/β transition peak of the troilite exhibits the temperature gradient evolved during atmospheric passage of a meteoroid. Moreover, the enthalpy changes of α/β transition were used to determine the troilite content in the meteorite samples (3.6 wt.%). Obtained data are in agreement with previous Leco method’s results, since NWA 6255 is relatively fresh find (W1) and troilite tends to oxidized quickly.