Spectropolarimetric signatures of Earth-like extrasolar planets

By D. Stam. 2007

154 citations recorded by the source corpus.

We present results of numerical simulations of flux F and degree of polarization P of light that is reflected by Earth–like extrasolar planets orbiting solar type stars. Our results are presented as functions of the wavelength (from 0.3 to 1.0 ?m, with 0.001 ?m spectral resolution) and as functions of the planetary phase angle. We use different surface coverages for our model planets, including vegetation and a Fresnel reflecting ocean, and clear and cloudy atmospheres. Our adding-doubling radiative transfer algorithm, which fully includes multiple scattering and polarization, only handles horizontally homogeneous planets, so we simulate fluxes and polarization of horizontally inhomogeneous planets by weighting results obtained for homogeneous planets. Like F, P of the reflected starlight is shown to depend strongly on the phase angle, on the composition and structure of the planetary atmosphere, on the reflective properties of the underlying surface, and on the wavelength, in particular in wavelength regions with gaseous absorption bands. The sensitivity of P to a planet’s physical properties appears to be different than that of F. Combining flux with polarization observations thus makes for a strong tool for characterizing extrasolar planets. The calculated total and polarized fluxes are made available through the CDS.

Subfields: Astronomy and Astrophysics, Atmospheric Science

View Paper: https://www.semanticscholar.org/paper/fa52123445c55898af8e8123033c15bd8ce2e5ed

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

In Atmospheric Science

Citations in the corpus

Exoplanet Biosignatures: A Review of Remotely Detectable Signs of Life (2017, background): “ has been shown that abiotic environmental factors such as mineral dust (West et al., 1997), scattering by particles in the atmosphere (Shkuratov et al., 2006), and the molecular absorption by gases (Stam, 2008; Takahashi et al., 2013; Miles-Pa´ez et al., 2014) can also produce positive linear polar”
SPHERE: the exoplanet imager for the Very Large Telescope (2019, background): “…scattering by aerosols are in atmospheres of solar system objects the dominant processes for producing strong scattering polarization at short wavelengths < 1 µm (Tomasko & Smith 1982; Smith & Tomasko 1984; Stam et al. 2004; Stam 2008; Schmid et al. 2006, 2011; Bazzon et al. 2013, 2014).”