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Small rocky planets, as well as larger planets that suffered extensive volatile loss, tend to be drier and have thinner atmospheres as compared to Earth. Such planets probably outnumber worlds better endowed with volatiles, being the most common habitable planets. For the subgroup of fast rotators following eccentric orbits, atmospheres suffer radiative forcing and their heat capacity provides a method for gauging atmospheric thickness and surface conditions. We further explore the model presented in a previous paper and apply it to real and hypothetical exoplanets in the habitable zone of various classes of stars, simulating atmospheric and orbital characteristics. For planetary eccentricities e ∼ 0.3, the forcing-induced hypothetical temperature variation would reach ∼80 K for airless planets and ∼10 K for planets with substantial atmospheres. For Kepler-186 f and Kepler-442 b, assuming e ∼ 0.1, temperature variations can reach ∼24 K. We also consider habitable exomoons in circular orbits around gas giants within the habitable zone, which suffer radiative forcing due to their epicyclic motion. We study several combinations of parameters for the characterization of planets (mass, eccentricity, and semimajor axis) and exomoons (mass, orbital radius, albedo, and atmospheric characteristics) for different stellar types. For e ∼ 0.3, exomoon temperature varies up to ∼90 K, while for ∼0.6 variations can reach ∼200 K. Such exomoons may plausibly retain their volatiles by continued volcanic activity fuelled by tidal dissipation. Although currently undetectable, such effects might be within reach of future Extremely Large Telescope-class telescopes and space missions with mid-infrared and coronagraphic capabilities. [ABSTRACT FROM AUTHOR]

We derive Teff and [Fe/H] for a sample of 72 nearby M-dwarfs with Hipparcos parallaxes and δ < +30. Spectra, acquired at the Observatório do Pico dos Dias, Brazil, have R = 10,000 and S/N ≳ 100 for nearly all targets in the λλ8380-8880 range. Atmospheric parameters were derived from VJHK colors and a system of spectral line indices calibrated against sample stars with interferometric Teff and [Fe/H] from detailed analysis of FGK binary companions. A PCA method of calibration yields internal errors within 70 K and 0.1 dex for Teff and [Fe/H]. For 18 stars we present the first Teff or [Fe/H] derivation in the literature. We compute the star's luminosities, calculate the position of their habitable zones and estimate that, were all of they to harbour rocky planets inside their HZ, 15-20 of these would be detectable by the E-ELT Planetary Camera and Spectrograph. [ABSTRACT FROM AUTHOR]