Mathematics – Logic
Scientific paper
Dec 2011
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011agufm.p11f1629y&link_type=abstract
American Geophysical Union, Fall Meeting 2011, abstract #P11F-1629
Mathematics
Logic
[6200] Planetary Sciences: Solar System Objects, [6207] Planetary Sciences: Solar System Objects / Comparative Planetology, [6296] Planetary Sciences: Solar System Objects / Extra-Solar Planets, [6297] Planetary Sciences: Solar System Objects / Instruments And Techniques
Scientific paper
Polarimetry is currently enjoying a rejuvenation in planetary, astrophysical and exobiology applications from characterization of various solar system objects (planetary atmospheres, comets, satellites, ring systems, asteroids, dust, etc.) to detection and characterization of exoplanets and identification of biological markers. Although ground-based observations of the planets and their satellites are restricted to small phase angles, important results have been obtained with polarimetry. Incident starlight is linearly polarized by planetary atmospheres due to multiple light scattering by atmospheric aerosols and hazes (sulphuric acid on Venus; dust storms and ice clouds on Mars; variations in hydrocarbon hazes from equator to poles on Jupiter, Saturn, Neptune and Uranus). In Saturn's rings, anisotropic multiple scattering effects are observed and exhibit variations often in few days or weeks, with mutual interactions and gravitational resulting in organized structures. The curves of polarization for atmosphereless Solar System objects (such as the Moon, planetary satellites and asteroids) are diagnostic of the micro-texture of the surface, and demonstrate that most of them have their surfaces covered with a regolith of fine material, a function of particle size and regolith packing density. These properties are a function of the composition of the parent bodies. An example is the recent discovery of a class of large inversion angle asteroids, displaying spinel features in their spectra and indicative of the oldest surfaces in the Solar System. Linear and circular polarization of comets provides information about the composition and wavelength dependence of the dust, indicative of new, active comets vs. older comets. Measuring the degree of linear polarization can diagnose physical conditions of the scattering surface and is complementary to photometry and spectroscopy for the remote analysis of small solar system objects. In addition, measuring the linear polarization of exoplanetary systems can detect exoplanets separate from their parent stars. Biological molecules exhibit an inherent handedness or circular polarization or chirality; search for chiral signatures on exo-Earths would identify astrobiological material. Even as the field of polarimetric observations is maturing as a technique for remote sensing, the modeling of polarimetric observations is not similarly mature. Recent efforts include characterization of light scattering by particles of complex shapes and structures to be calculated; vector radiative transfer equation for optically thick media to be solved; with approximations to model closely packed particulate media or regoliths. The synergy between the new modeling techniques and increased use of polarization as a remote sensing technique provide opportunities to understand our solar system and other planetary systems.
No associations
LandOfFree
Remote Sensing and Modeling of Polarimetric Signatures of Solar System Objects does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Remote Sensing and Modeling of Polarimetric Signatures of Solar System Objects, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Remote Sensing and Modeling of Polarimetric Signatures of Solar System Objects will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-867807