English
Related papers

Related papers: Global Mapping of Surface Composition on an Exo-Ea…

200 papers

We develop a new retrieval scheme for obtaining two-dimensional surface maps of exoplanets from scattered light curves. In our scheme, the combination of the L1-norm and Total Squared Variation, which is one of the techniques used in sparse…

Earth and Planetary Astrophysics · Physics 2020-06-17 Masataka Aizawa , Hajime Kawahara , Siteng Fan

Photometric variation of a directly imaged planet contains information on both the geography and spectra of the planetary surface. We propose a novel technique that disentangles the spatial and spectral information from the multi-band…

Earth and Planetary Astrophysics · Physics 2020-05-13 Hajime Kawahara

Planned missions will spatially resolve temperate terrestrial planets from their host star. Although reflected light from such a planet encodes information about its surface, it has not been shown how to establish surface characteristics of…

Earth and Planetary Astrophysics · Physics 2015-06-12 Nicolas B. Cowan , Talia E. Strait

Scattered lights from terrestrial exoplanets provide valuable information about the planetary surface. Applying the surface reconstruction method proposed by Fujii et al. (2010) to both diurnal and annual variations of the scattered light,…

Earth and Planetary Astrophysics · Physics 2011-01-07 Hajime Kawahara , Yuka Fujii

Unmixing the disk-integrated spectra of exoplanets provides hints about heterogeneous surfaces that we cannot directly resolve in the foreseeable future. It is particularly important for terrestrial planets with diverse surface compositions…

Earth and Planetary Astrophysics · Physics 2017-10-31 Yuka Fujii , Jacob Lustig-Yaeger , Nicolas B. Cowan

Finding potential life harboring exo-Earths is one of the aims of exoplanetary science. Detecting signatures of life in exoplanets will likely first be accomplished by determining the bulk composition of the planetary atmosphere via…

Earth and Planetary Astrophysics · Physics 2021-02-03 A. Asensio Ramos , E. Pallé

As a test-bed for future investigations of directly imaged terrestrial exoplanets, we present the recovery of the surface components of the Earth from multi-band diurnal light curves obtained with the EPOXI spacecraft. We find that the…

Earth and Planetary Astrophysics · Physics 2015-05-27 Yuka Fujii , Hajime Kawahara , Yasushi Suto , Satoru Fukuda , Teruyuki Nakajima , Timothy A. Livengood , Edwin L. Turner

This work concerns a detailed review of data analysis methods used for remotely sensed images of large areas of the Earth and of other solid astronomical objects. In detail, it focuses on the problem of inferring the materials that cover…

Instrumentation and Methods for Astrophysics · Physics 2025-07-22 Alfredo Gimenez Zapiola , Andrea Boselli , Alessandra Menafoglio , Simone Vantini

Future telescopes will characterize rocky exoplanets in reflected light, revealing their albedo, which depends on surface, cloud, and atmospheric properties. Identifying these features is crucial for assessing habitability. We present…

Earth and Planetary Astrophysics · Physics 2025-04-09 Giulia Roccetti , Claudia Emde , Michael F. Sterzik , Mihail Manev , Julia V. Seidel , Stefano Bagnulo

Context. Clouds have already been detected in exoplanetary atmospheres. They play crucial roles in a planet's atmosphere and climate and can also create ambiguities in the determination of atmospheric parameters such as trace gas mixing…

Earth and Planetary Astrophysics · Physics 2017-11-22 Loïc Rossi , Daphne Stam

This paper presents a new Bayesian collaborative sparse regression method for linear unmixing of hyperspectral images. Our contribution is twofold; first, we propose a new Bayesian model for structured sparse regression in which the…

Computation · Statistics 2023-07-19 Yoann Altmann , Marcelo Pereyra , Jose Bioucas-Dias

Transit spectroscopy is a powerful tool to decode the chemical composition of the atmospheres of extrasolar planets. In this paper we focus on unsupervised techniques for analyzing spectral data from transiting exoplanets. We demonstrate…

Earth and Planetary Astrophysics · Physics 2022-01-11 Konstantin T. Matchev , Katia Matcheva , Alexander Roman

Hyperspectral unmixing, the process of estimating a common set of spectral bases and their corresponding composite percentages at each pixel, is an important task for hyperspectral analysis, visualization and understanding. From an…

Computer Vision and Pattern Recognition · Computer Science 2014-11-18 Feiyun Zhu , Ying Wang , Bin Fan , Gaofeng Meng , Shiming Xiang , Chunhong Pan

This paper presents a semi-supervised hyperspectral unmixing solution that integrate the spatial information in the abundance estimation procedure. The proposed method is applied on a nonlinear model based on polynomial postnonlinear mixing…

Signal Processing · Electrical Eng. & Systems 2018-03-05 Fahime Amiri , Mohammad Hossein. Kahaei

Reflected light photometry of terrestrial exoplanets could reveal the presence of oceans and continents, hence placing direct constraints on the current and long-term habitability of these worlds. Inferring the albedo map of a planet from…

Earth and Planetary Astrophysics · Physics 2022-01-19 Lucas Teinturier , Nicholas Vieira , Elisa Jacquet , Juliette Geoffrion , Youssef Bestavros , Dylan Keating , Nicolas B. Cowan

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

In the near-future, dedicated telescopes observe Earth-like exoplanets in reflected light, allowing their characterization. Because of the huge distances, every exoplanet will be a single pixel, but temporal variations in its spectral flux…

Earth and Planetary Astrophysics · Physics 2022-08-10 K. Meinke , D. M. Stam , P. M. Visser

Undirected graphical models have been successfully used to jointly model the spatial and the spectral dependencies in earth observing hyperspectral images. They produce less noisy, smooth, and spatially coherent land cover maps and give top…

Computer Vision and Pattern Recognition · Computer Science 2018-12-05 Utsav B. Gewali , Sildomar T. Monteiro

Characterizing the surfaces of rocky exoplanets via the scattered light will be an essential challenge to investigate the existence of life on habitable exoplanets. We present a simple reconstruction method for fractional areas of different…

Earth and Planetary Astrophysics · Physics 2014-11-20 Y. Fujii , H. Kawahara , Y. Suto , A. Taruya , S. Fukuda , T. Nakajima , E. L. Turner

Spectral retrieval techniques are currently our best tool to interpret the observed exoplanet atmospheric data. Said techniques retrieve the optimal atmospheric components and parameters by identifying the best fit to an observed…

Earth and Planetary Astrophysics · Physics 2020-10-21 Kai Hou Yip , Ingo P. Waldmann , Angelos Tsiaras , Giovanna Tinetti
‹ Prev 1 2 3 10 Next ›