EXOTOPO The data consists in topographic maps of synthetic 3D bodies generated by a 3 parameters statistical model : the fractionally integrated flux (FiF) (Lavallée et al 1993) adapted for spherical coordinates (Landais et al., 2018). The 3 parameters are the following : H : degree of smoothness C1 : degree of intermittency alpha : degree of multifractality Detailed information about the fractionally integrated flux model can be found in Lavallée et al 1993. We adapted the model on a spherical geometry (Landais et al 2018) and wish to provide in this archive some example of the model output.The synthetic topographic maps consist in 2001x4000 lat-long grids that contained elevation data of the global surface with a simple cylindrical projection. Combined to a radius that can be freely chosen, each grid may be used to construct a 3-D shape of a planet-like or asteroid-like body. We aimed to illustrate the impact of a variation of H (degree of roughness), C1 (degree of intermittency) and alpha (degree of multifractality) for a single Random Seed. Hence the map covers the combination of values of alpha = {1.4:0.1:2.0} (7 values), H = {0.1:0.1:1.0} (10 values) and C1 ={0:0.05:0.2} (5 values) with one unique random seed identifier S=07, (lower id refers to former dataset: http://dx.doi.org/10.14768/20181024001.1). Additionally, we compute the same simulations with alpha=1.9 H=0.5 C1=0.1 corresponding to the Earth set of parameters with 10 various random seeds id S=08 to S=17. Data are distributed in two directories: Various Parameters with subdirectories grouped by Alpha Value and Various Random Seeds data with Earth-like parameters. Two kind of files are present : 1) Fits files containing topographic maps represented as a lat-long grid. The topographic map containing altitude value scaled between -1000 and +1000. Topography nomenclature : S{seed id}_A{value of alpha x10}_C{value of C1 x100}_H{value of H x10}_LAT{latitude sampling}_LON{longitude sampling}_TOPO.fits - Example : S07_A14_C00_H06_LAT2001_LON4000TOPO.fits contains a 5000x10000 double lat-long map with a random seed identified by : "07", ALPHA =1.4, C1=0.0 and H=0.6 - Example : S12_A19_C10_H05_LAT2001_LON4000TOPO.fits contains a 5000x10000 double lat-long map with a random seed identified by : "12", ALPHA =1.9, C1=1.0 and H=0.5 The models parameters are included in the comments of the Fits header - nb_lat : size of the latitude sampling - nb_long : size of the longitude sampling - alpha : degree of multifractality - C1 : degree of intermittency - H : degree of smoothness - idSeed : the identifier of the random seed - Seed : Value of the random Seed used for the simulation 2) png files into the subdirectories */Textures containing texture maps to be applied on the topography. As our statistical model mainly consists in a control of roughness at different scales and location, the main goal of the texture map is to be visually significant in terms of roughness, reflecting the juxtaposition of rough and smooth places. We make use of the classic method of Hill-shading that consists in computing the scalar product between local slopes and a constant light direction. Given the spherical geometry, only a portion of the synthetic body can be clearly visible under a specific light direction. For each topographic map we provide hill-shade textures in an arbitrarily chosen light direction. For each file, a texture map as a shade of gray and one which tends to reproduce the color of an earth-like planet are given. Additionally, we provide the texture colormaps without hill-shading in each case. As a result, there are four distinct texture maps for each field with the following nomenclature : Texture nomenclature : S{seed id}_A{value of alpha x10}_C{value of C1 x100}_H{value of H x10}_LAT{latitude sampling}_LON{longitude sampling}{"COLO" or "GRAY"}{"SHADE" or "FLAT"}.png - Example : S07_A14_C20_H02_LAT2001_LON4000COLOSHAD.png : 2001x4000x3 uint8 texture image with hillshading and earthlike colormap. - Example : S07_A14_C20_H02_LAT2001_LON4000COLOFLAT.png : 2001x4000x3 uint8 texture image without hillshading and earthlike colormap. - Example : S07_A14_C20_H10_LAT2001_LON4000GRAYSHAD.png : 2001x4000x3 uint8 texture image with hillshading and shade-of-gray colormap The GRAYFLAT texture is the constant gray texture to apply the hill-shade for asteroid-like bodies, as it it the same for all the parameters, it is located into the file TextureGRAYFLAT/LAT2001_LON4000GRAYFLAT.png 3) png files containing quicklooks (light png files) are into the subdirectories */Thumbnails. 2 types of quicklooks are provided: - Texture maps previously described resized to 200x400 pixels Thumbnail Texture nomenclature : Thumbnail_S{seed id}_A{value of alpha x10}_C{value of C1 x100}_H{value of H x10}_LAT{latitude sampling}_LON{longitude sampling}{"COLO" or "GRAY"}{"SHADE" or "FLAT"}.png - png files representing the 3D plot of the body with hillshading texture for the grayscale colormap and the colorized one one. Thumbnail TOPO nomenclature : Thumbnail_S{seed id}_A{value of alpha x10}_C{value of C1 x100}_H{value of H x10}_LAT{latitude sampling}_LON{longitude sampling}{"COLO" or "GRAY"}TOPO.png Conclusion : the folder is composed of topographic maps, texture maps and quicklooks. Ideally, the users should be able to switch between random seeds and values of H, alpha and C1. references : - Landais, F., Schmidt, F., and Lovejoy, S, (2018) Topography of exoplanets, MNRAS - Lavallée, D., Lovejoy, S., Schertzer, D., & Ladoy, P. (1993). Nonlinear variability and landscape topography: analysis and simulation. Fractals in geography, edited by L. De Cola and N. Lam, Prentice-Hall, New Jersey, 158-192.