Spatial Characterization of MAC, a High-Resolution Optical Earth Observation Camera for Small Satellites

Abstract. Small satellites play an increasing role in earth observation. This article evaluates different possibilities of utilizing data from Planet’s SkySat and PlanetScope satellites constellations for derivation of digital elevation models. While SkySat provides high resolution image data with a ground sampling distance of up to 50 cm, the PlanetScope constellation consisting of Dove 3U cubesats provide images with a resolution of around 4 m. The PlanetScope acquisition strategy was not designed for stereo acquisitions, but for daily acquisition of nadir viewing imagery. Multiple different products can be acquired by the SkySat satellites: Collects covering an area of usually 12 by 6 km, tri-stereo collects and video products with a framerate of 30 Hz. This study evaluates DSM generation using a Semi-Global Matching from multi date stereo pairs for SkySat and PlanetScope, and the dedicated Video and tri-stereo SkySat acquisitions. DSMs obtained by merging many PlanetScope across track stereo pairs show an normalized median deviation against LiDaR first pulse data of 5.2 meter over diverse landcover at the test sites around the city of Terrassa in Catalonia, Spain. SkySat tri-stereo products with 80 cm resolution reach an NMAD of 1.3 m over Terrassa.

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Multifractal analysis for spatial characterization of high resolution Sentinel-2/MAJA products in Southwestern France

Remote Sensing of Environment ◽

10.1016/j.rse.2021.112859 ◽

2022 ◽

Vol 270 ◽

pp. 112859

Author(s):

M. Neuhauser ◽

S. Verrier ◽

S. Mangiarotti

Keyword(s):

High Resolution ◽

Multifractal Analysis ◽

Spatial Characterization ◽

Sentinel 2

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Cold-seep habitat mapping: High-resolution spatial characterization of the Blake Ridge Diapir seep field

Deep Sea Research Part II Topical Studies in Oceanography ◽

10.1016/j.dsr2.2013.02.008 ◽

2013 ◽

Vol 92 ◽

pp. 183-188 ◽

Cited By ~ 21

Author(s):

Jamie K.S. Wagner ◽

Molly H. McEntee ◽

Laura L. Brothers ◽

Christopher R. German ◽

Carl L. Kaiser ◽

...

Keyword(s):

High Resolution ◽

Habitat Mapping ◽

Cold Seep ◽

Spatial Characterization ◽

Blake Ridge

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Spatial characterization of the trailing and leading limbs of WASP-76b: Detection of H2O and HCN at high-resolution

10.5194/epsc2021-563 ◽

2021 ◽

Author(s):

Alejandro Sánchez López ◽

Rico Landman ◽

Núria Casasayas Barris ◽

Aurora Kesseli ◽

Ignas Snellen

Keyword(s):

High Resolution ◽

Extreme Temperature ◽

Temporal Variations ◽

Time Variability ◽

Small Range ◽

Hot Jupiters ◽

Spatial Characterization ◽

Weak Evidence ◽

Dependent Absorption

<p class="p1">Extreme temperature contrasts between the day and nightside of ultra-hot Jupiters (UHJ) result in significantly asymmetric atmospheres, with a region of extreme atmospheric expansion appearing over a small range of latitudes around the terminator. Over the course of a transit, WASP-76 b rotates by about 30&#176; and hence temporal variations of the observable atmosphere could significantly affect the detectability of its constituents. Specifically, the trailing limb of this planet allows us to probe a significant portion of the inflated dayside, resulting in a higher atmospheric detectability. This geometric effect could mimic the observed time-variability of absorption signals due to condensation in the nightside of these planets, which has been recently reported for neutral iron in WASP-76 b. By studying molecules that are not expected to condense in the nightside of UHJs (~1000K), we can isolate the possible effect of different day and nightside scale heights. Here, we will analyze a stronger water vapor signal during the egress of the planet than at ingress, which cannot be explained by condensation and suggests that the extreme geometry of UHJ manifests itself as time-dependent absorption signals. Additionally, we report a redshifted HCN signature arising from the leading limb (i.e., observable in the first half of the transit and absent from the second half) and a weak evidence of ammonia using high-resolution observations of WASP-76 b with CARMENES.</p>

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Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074768 ◽

1983 ◽

Vol 41 ◽

pp. 194-195

Author(s):

D. F. Blake ◽

L. F. Allard ◽

D. R. Peacor

Keyword(s):

High Resolution ◽

Marine Invertebrates ◽

Sea Urchins ◽

Structural Features ◽

Sea Stars ◽

High Resolution Tem ◽

Relationship Of ◽

The Relationship ◽

Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

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High-resolution electron microscopy of nanostructured materials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100137239 ◽

1995 ◽

Vol 53 ◽

pp. 172-173

Author(s):

M. José-Yacamán

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Grain Boundaries ◽

Nanostructured Materials ◽

High Resolution Electron Microscopy ◽

Hrem Image ◽

Small Particles ◽

Resolution Electron ◽

Nanophase Materials

Electron microscopy is a fundamental tool in materials characterization. In the case of nanostructured materials we are looking for features with a size in the nanometer range. Therefore often the conventional TEM techniques are not enough for characterization of nanophases. High Resolution Electron Microscopy (HREM), is a key technique in order to characterize those materials with a resolution of ~ 1.7A. High resolution studies of metallic nanostructured materials has been also reported in the literature. It is concluded that boundaries in nanophase materials are similar in structure to the regular grain boundaries. That work therefore did not confirm the early hipothesis on the field that grain boundaries in nanostructured materials have a special behavior. We will show in this paper that by a combination of HREM image processing, and image calculations, it is possible to prove that small particles and coalesced grains have a significant surface roughness, as well as large internal strain.

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High-resolution transmission electron microscopic study of highly oxygen doped silicon layer

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100155438 ◽

1989 ◽

Vol 47 ◽

pp. 692-693

Author(s):

H. Takaoka ◽

M. Tomita ◽

T. Hayashi

Keyword(s):

High Resolution ◽

Oxygen Concentration ◽

Silicon Layer ◽

Detailed Structure ◽

Electron Microscopic ◽

Cross Sectional ◽

Transmission Electron ◽

Doped Silicon ◽

Argon Ion

High resolution transmission electron microscopy (HRTEM) is the effective technique for characterization of detailed structure of semiconductor materials. Oxygen is one of the important impurities in semiconductors. Detailed structure of highly oxygen doped silicon has not clearly investigated yet. This report describes detailed structure of highly oxygen doped silicon observed by HRTEM. Both samples prepared by Molecular beam epitaxy (MBE) and ion implantation were observed to investigate effects of oxygen concentration and doping methods to the crystal structure.The observed oxygen doped samples were prepared by MBE method in oxygen environment on (111) substrates. Oxygen concentration was about 1021 atoms/cm3. Another sample was silicon of (100) orientation implanted with oxygen ions at an energy of 180 keV. Oxygen concentration of this sample was about 1020 atoms/cm3 Cross-sectional specimens of (011) orientation were prepared by argon ion thinning and were observed by TEM at an accelerating voltage of 400 kV.

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