Mineral dust increases the habitability of terrestrial planets but confounds biomarker detection

Identification of habitable planets beyond our solar system is a key goal of current and future space missions. Yet habitability depends not only on the stellar irradiance, but equally on constituent parts of the planetary atmosphere. Here we show, for the first time, that radiatively active mineral dust will have a significant impact on the habitability of Earth-like exoplanets. On tidally-locked planets, dust cools the day-side and warms the night-side, significantly widening the habitable zone. Independent of orbital configuration, we suggest that airborne dust can postpone planetary water loss at the inner edge of the habitable zone, through a feedback involving decreasing ocean coverage and increased dust loading. The inclusion of dust significantly obscures key biomarker gases (e.g. ozone, methane) in simulated transmission spectra, implying an important influence on the interpretation of observations.We demonstrate that future observational and theoretical studies of terrestrial exoplanets must consider the effect of dust

Planetary mapping for landing sites selection: The mars case study

The selection of a landing site on a planetary body is a multistep process that involves both the fulfillment of several engineering constraints and the accomplishment of scientific requirements. In this chapter, we will show how the simultaneous production and exploitation of different GIS maps depicting these criteria are pivotal in the landing site selection. Indeed, all of such constraints are presently evaluated through the use of GIS-based software. To show this, we will focus on the Martian site identification outline, providing multiple real examples taken from two ongoing study cases, i.e., the Simud Vallis landing site proposed by Pajola et al. (Icarus 268:355\u2013381, 2016a) for the ESA ExoMars rover and the Eridania landing site proposed by Pajola et al. (Icarus 275:163\u2013182, 2016b) for the NASA Mars 2020 landing site selection

Thermodynamics of fluid mixtures near to and far from the critical region

A theory for an equation of state for simple fluid mixtures valid both near to and far from critical points is presented. The base equation of state obtained from integral-equation theory using the mean-spherical approximation is used to compute the contribution of short-wavelength fluctuations to the free energy of the fluid mixture. Wilson's phase-space cell approximation, as extended by White, is used to compute the contribution of long-wavelength fluctuations.The resulting theory possesses nonclassic critical exponents similar to those observed experimentally. Far from the critical region, where long-wavelength fluctuations are not important, the theory reduces to that corresponding to the base equation of state. The complete theory is used to represent the thermodynamic properties and phase behavior of binary mixtures of methane, carbon dioxide and n-butane.In the critical region, agreement with experiment is dramatically improved upon, adding to the base equation of state corrections from long-wavelength fluctuations