Investigating circular patterns in linear polarization observations of Venus

Investigating circular patterns in linear polarization observations of Venus

Mahapatra, G. (TU Delft Astrodynamics & Space Missions)
Stam, D.M. (TU Delft Astrodynamics & Space Missions)
Rossi, L.C.G. (TU Delft Astrodynamics & Space Missions)
Rodenhuis, M. (Universiteit Leiden)
Snik, Frans (Universiteit Leiden)
Keller, C.U. (Universiteit Leiden)

2017

In this work, we analyse linear polarization data of the planet at a distance, obtained with the Extreme Polarimeter (ExPo) on the William Herschel Telescope
on La Palma. These spatially resolved, high-accuracy polarization observations of Venus show faint circular patterns centered on the sub-solar point that are absent in the flux observations. So far, careful analyses have ruled out instrumental effects which leaves us to wonder about atmospheric properties on Venus as the cause of the circular patterns. Using numerical simulations of the flux and polarization of sunlight that is reflected by Venus, we have investigated the relation between the observed patterns and several atmospheric properties, such as variations in particle sizes, composition, density and altitude. We discuss the plausibility of the possible causes in the view of the current knowledge
of the composition and dynamical processes in Venus’s atmosphere.

http://resolver.tudelft.nl/uuid:29add911-d613-4b96-9807-876ab2cafd9d

European Planetary Science Congress 2017, 2017-09-17 → 2017-09-22, Riga, Latvia

Institutional Repository

abstract

© 2017 G. Mahapatra, D.M. Stam, L.C.G. Rossi, M. Rodenhuis, Frans Snik, C.U. Keller