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Recording and identifying faint objects through atmospheric scattering media by an optical system are fundamentally interesting and technologically important. In this work, we introduce a comprehensive model that incorporates contributions…

Optics · Physics 2024-04-24 Libang Chen , Jun Yang , Lingye Chen , Yuyang Shui , Yikun Liu , Jianying Zhou

Transmission spectra of exoplanetary atmospheres have been used to infer the presence of clouds/hazes. Such inferences are typically based on spectral slopes in the optical deviant from gaseous Rayleigh scattering or low-amplitude spectral…

Earth and Planetary Astrophysics · Physics 2017-08-31 Arazi Pinhas , Nikku Madhusudhan

The accuracy of ground-based astronomical photometry is limited by two factors: photon statistics and stellar scintillation arising when star light passes through Earth's atmosphere. This paper examines the theoretical role of the outer…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 Victor Kornilov

We develop an inversion technique of annual scattered light curves to sketch a two-dimensional albedo map of exoplanets in face-on orbits. As a test-bed for future observations of extrasolar terrestrial planets, we apply this mapping…

Earth and Planetary Astrophysics · Physics 2011-09-16 Hajime Kawahara , Yuka Fujii

Future space-based direct imaging missions will perform low-resolution (R$<$100) optical (0.3-1~$\mu$m) spectroscopy of planets, thus enabling reflected spectroscopy of cool giants. Reflected light spectroscopy is encoded with rich…

Earth and Planetary Astrophysics · Physics 2021-04-14 Sagnick Mukherjee , Natasha E. Batalha , Mark S. Marley

The properties of synthetic CO emission from 3D simulations of forming molecular clouds are studied within the SILCC-Zoom project. Since the time scales of cloud evolution and molecule formation are comparable, the simulations include a…

Emission spectroscopy is an invaluable tool for probing the atmospheres of brown dwarfs and exoplanets, but interpretations based on flux spectra alone often suffer from degeneracies among temperature structure, chemical composition, and…

Earth and Planetary Astrophysics · Physics 2025-12-16 Fei Wang , Yuka Fujii , Ben Burningham , Jinping He

Reliable and exact assessment of visibility is essential for safe air traffic. In order to overcome the drawbacks of the currently subjective reports from human observers, we present an approach to automatically derive visibility measures…

Computer Vision and Pattern Recognition · Computer Science 2015-05-21 Jean-Philippe Andreu , Stefan Mayer , Karlheinz Gutjahr , Harald Ganster

The Sun has long been considered a constant star, to the extent that its total irradiance was termed the solar constant. It required radiometers in space to detect the small variations in solar irradiance on timescales of the solar rotation…

Solar and Stellar Astrophysics · Physics 2015-06-11 Sami K. Solanki , Yvonne C. Unruh

The apparent brightness of satellites is calculated as a function of satellite position as seen by a ground-based observer in darkness. Both direct illumination of the satellite by the Sun as well as indirect illumination due to reflection…

Instrumentation and Methods for Astrophysics · Physics 2023-10-13 Forrest Fankhauser , J. Anthony Tyson , Jacob Askari

We model the impact of non-uniform cloud cover on transit transmission spectra. Patchy clouds exist in nearly every solar system atmosphere, brown dwarfs, and transiting exoplanets. Our major findings suggest that fractional cloud coverage…

Earth and Planetary Astrophysics · Physics 2016-04-06 Michael R. Line , Vivien Parmentier

Clouds have a strong impact on the climate of planetary atmospheres. The potential scattering greenhouse effect of CO2 ice clouds in the atmospheres of terrestrial extrasolar planets is of particular interest because it might influence the…

Earth and Planetary Astrophysics · Physics 2017-06-16 Daniel Kitzmann

Magnetic features on the surfaces of cool stars cause variations of their brightness. Such variations have been extensively studied for the Sun. Recent planet-hunting space telescopes allowed measuring brightness variations in hundred…

Solar and Stellar Astrophysics · Physics 2020-04-15 N. -E. Nèmec , A. I. Shapiro , N. A. Krivova , S. K. Solanki , R. V. Tagirov , R. H. Cameron , S. Dreizler

Marine stratocumulus clouds play a critical role in the Earth's climate system. They display an amazing array of complex behaviors at many different spatiotemporal scales. Precipitation in these clouds is in general very light, but it is…

Atmospheric and Oceanic Physics · Physics 2015-06-30 Tianle Yuan

Soiling, which consists of dust, dirt and particles accumulated on the surface of conventional or concentrator photovoltaic modules, absorbs, scatters, and reflects part of the incoming sunlight. Therefore, it reduces the amount of energy…

Systems and Control · Electrical Eng. & Systems 2021-03-03 Eduardo F. Fernandez , Daniel Chemisana , Leonardo Micheli , Florencia Almonacid

The estimation of total solar irradiance falling on the earth's surface is important in the field of solar energy generation and forecasting. Several clear-sky solar radiation models have been developed over the last few decades. Most of…

Atmospheric and Oceanic Physics · Physics 2017-08-30 Soumyabrata Dev , Shilpa Manandhar , Yee Hui Lee , Stefan Winkler

Optical sections of the cornea are obtained by illumination with a collimated beam expanded in a fan shape by a small rotary cylindrical lens. The light diffused from the cornea is observed by two cameras and processed in order to yield the…

Medical Physics · Physics 2007-05-23 Jose B. Almeida , Sandra Franco

The quality of images of the Sun obtained from the ground are severely limited by the perturbing effect of the turbulent Earth's atmosphere. The post-facto correction of the images to compensate for the presence of the atmosphere require…

Solar and Stellar Astrophysics · Physics 2018-12-05 A. Asensio Ramos , J. de la Cruz Rodriguez , A. Pastor Yabar

With Planck and Herschel, we now have the spectral coverage and angular resolution required to observe dense and cold molecular clouds. As these clouds are optically thick at short wavelength but optically thin at long wavelength, it is…

The unprecedented precision of broadband stellar photometry achieved with the planet-hunting missions CoRoT and \textit{Kepler} initiated a new era in examining the magnetically-driven brightness variations of hundreds of thousands of…

Solar and Stellar Astrophysics · Physics 2021-06-25 Nina-Elisabet Nèmec