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  • Data (13)
  • News (17)
  • Missions (2)
  • Events (10)
  • Tools (3)
  • Activities (3)
  • Documents (1200)
  • News - Thematic area articles

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    Transforming space data into climate action

    ESA’s Earth observation activities are playing a key role in the revitalised global drive to combat climate change.

  • Document - Technical Note

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    The RA-2 On-Board Tracker and its Autonomous Adaptable Resolution

    This technical note describes the complete functionality of the RA-2 on-board Tracker and how its Resolution Selection Logic (RSL) works. It gives a detailed analysis of the algorithm and its configuration parameters.

  • Document - General Reference

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    The Envisat Radar Altimeter System (RA-2)

    This article was published in the ESA Bulletin Nr. 98 and givesdetails on RA-2 and on its role in the ENVISAT mission.

  • Document - General Reference

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    Taking-the-Measure-of-Earth-Fifteen-Years-of-Progress-in-Radar-Altimetry.pdf

    This article is extracted from ESA Bulletin Nr. 128.

  • Data - Sample Data (Open)

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    SkySat Sample Data

    Download free SkySat sample datasets to preview products available for this mission.

  • Data - Project Proposal (Restrained)

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    SkySat Full Archive and New Tasking

    The SkySat Level 2B Basic Scene, Level 3B Ortho Scene and Level 3B Consolidated full archive and new tasking products are available as part of Planet imagery offer. The SkySat Basic Scene product is uncalibrated and in a raw digital number format, not corrected for any geometric distortions inherent in the imaging process. Rational Polynomial Coefficients (RPCs) is provided to enable orthorectification by the user. Basic Scene Product Components and Format Processing Levels Analytic (unorthorectified, radiometrically corrected, multispectral BGRN) Analytic DN (unorthorectified, multispectral BGRN) Panchromatic DN (unorthorectified, panchromatic) Product Components and Format Image File (GeoTIFF format) Metadata File (JSON format) Rational Polynomial Coefficients (Text File) UDM File (GeoTIFF format) Image Configuration 4-band Analytic DN Image (Blue, Green, Red, NIR) 1-band Panchromatic DN Image (Pan) Ground Sampling Distance 3.7 m at nadir (average at reference altitude 475 km) Ground Sampling Distance (nadir) Panchromatic 0.86m and Multispectral 1.0m for SkySat-1&2 Panchromatic 0.65m and Multispectral 0.8m for SkySat-3 to 13 (0.72 m and 1.0m for data acquired before 30/06/2020) Accuracy <50 m RMSE The SkySat Ortho Scene is sensor- and geometrically-corrected (by using DEMs with a post spacing of between 30 and 90 meters) and is projected to a cartographic map projection; the accuracy of the product will vary from region to region based on available GCPs. Different products are available: The SkySat Visual Ortho Scene product is orthorectified, pansharpened, and color-corrected (using a color curve) 3-band RGB Imagery The SkySat Pansharpened Multispectral Scene product is orthorectified, pansharpened 4-band BGRN Imagery The SkySat Analytic DN Ortho Scene product is orthorectified, multispectral BGRN, uncalibrated, digital number imagery product. The product has been processed to remove distortions caused by terrain; It eliminates the perspective effect on the ground (not on buildings), restoring the geometry of a vertical shot. Transformation to at-sensor radiance is not included The SkySat Panchromatic DN Ortho Scene product is orthorectified, panchromatic, uncalibrated, digital number imagery product. It has a finer GSD than the Analytic Product. Transformation to at-sensor radiance is not included. The SkySat Analytic Ortho Scene are calibrated multispectral imagery products with radiometric corrections applied to correct for any sensor artifacts and transformation to top-of-atmosphere radiance. The SkySat Consolidated Product are Ortho Collect product created by composing ~60 SkySat Ortho Scenes (Visual, Pansharpened Multispectral, Analytic DN, Panchromatic DN) along an imaging strip into segments Ortho Scene Product Components and Format Visual Ortho Pansharpened Multispectral Analytic DN Ortho Panchromatic DN Ortho Analytic Ortho Product Components and Format Image File (GeoTIFF format) Metadata File (JSON format) Rational Polynomial Coefficients (Text File) UDM File (GeoTIFF format) Image File (GeoTIFF) Metadata File (JSON format) Rational Polynomial Coefficients (Text File) UDM File (GeoTIFF format) Image File (GeoTIFF format) Metadata File (JSON format) Rational Polynomial Coefficients (Text File) UDM File (GeoTIFF format) Image File (GeoTIFF format) Metadata File (JSON format) Rational Polynomial Coefficients (Text File) UDM File (GeoTIFF format) Image File (GeoTIFF format) Metadata File (JSON format) Rational Polynomial Coefficients (Text File) UDM File (GeoTIFF format) Image Configuration 3-band Pansharpened Image (PS Red, PS Green, PS Blue) 4-band Pansharpened Image (PS Blue, PS Green, PS Red, PS NIR) 4-band Analytic DN Image (B, G, R, N) 1-band Panchromatic Image 4-band Analytic Image (B, G, R, N) Ground Sampling Distance 50 cm 50 cm 50 cm 50 cm 50 cm Projection UTM WGS84 UTM WGS84 UTM WGS84 UTM WGS84 UTM WGS84 Accuracy <10 m RMSE <10 m RMSE <10 m RMSE <10 m RMSE radiometric accuracy: +/- 5% Relative accuracy at < 10 degrees off-nadir angle As per ESA policy, very high-resolution imagery of conflict areas cannot be provided.

  • Data - Fast Registration with approval (Restrained)

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    SkySat ESA archive

    The SkySat ESA archive collection consists of SkySat products requested by ESA supported projects over their areas of interest around the world and that ESA collected over the years. The dataset regularly grows as ESA collects new products. Two different product types are offered, Ground Sampling Distance at nadir up to 65 cm for panchromatic and up to 0.8m for multi-spectral. EO-SIP Product Type Product Description Content SSC_DEF_SC Basic and Ortho scene Level 1B 4-bands Analytic /DN Basic scene Level 1B 4-bands Panchromatic /DN Basic scene Level 1A 1-band Panchromatic DN Pre Sup resolution Basic scene Level 3B 3-bands Visual Ortho Scene Level 3B 4-bands Pansharpened Multispectral Ortho Scene Level 3B 4-bands Analytic/DN/SR Ortho Scene Level 3B 1-band Panchromatic /DN Ortho Scene SSC_DEF_CO Ortho Collect Visual 3-band Pansharpened Image Multispectral 4-band Pansharpened Image Multispectral 4-band Analytic/DN/SR Image (B, G, R, N) 1-band Panchromatic Image The Basic Scene product is uncalibrated, not radiometrically corrected for atmosphere or for any geometric distortions inherent in the imaging process: Analytic - unorthorectified, radiometrically corrected, multispectral BGRN Analytic DN - unorthorectified, multispectral BGRN Panchromatic - unorthorectified, radiometrically corrected, panchromatic (PAN) Panchromatic DN - unorthorectified, panchromatic (PAN) L1A Panchromatic DN - unorthorectified, pre-super resolution, panchromatic (PAN) The Ortho Scene product is sensor and geometrically corrected, and is projected to a cartographic map projection: Visual - orthorectified, pansharpened, and colour-corrected (using a colour curve) 3-band RGB Imagery Pansharpened Multispectral - orthorectified, pansharpened 4-band BGRN Imagery Analytic SR - orthorectified, multispectral BGRN. Atmospherically corrected Surface Reflectance product. Analytic - orthorectified, multispectral BGRN. Radiometric corrections applied to correct for any sensor artifacts and transformation to top-of-atmosphere radiance. Analytic DN - orthorectified, multispectral BGRN, uncalibrated digital number imagery product Radiometric corrections applied to correct for any sensor artifacts Panchromatic - orthorectified, radiometrically correct, panchromatic (PAN) Panchromatic DN - orthorectified, panchromatic (PAN), uncalibrated digital number imagery product The Ortho Collect product is created by composing SkySat Ortho Scenes along an imaging strip. The product may contain artifacts resulting from the composing process, particular offsets in areas of stitched source scenes. Spatial coverage: Check the spatial coverage of the collection on a map available on the Third Party Missions Dissemination Service. As per ESA policy, very high-resolution imagery of conflict areas cannot be provided.

  • Mission - Third Party Missions

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    SkySat

    SkySat is a constellation of high-resolution Earth imaging satellites from the commercial company Planet Labs.

  • Data - EO Sign In Authentication (Open)

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    Sea Ice Thematic Data Product [ALT_TDP_SI]

    This is the Sea Ice Thematic Data Product (TDP) V1 resulting from the ESA FDR4ALT project and containing the sea ice related geophysical parameters, along with associated uncertainties: snow depth, radar and sea-ice freeboard, sea ice thickness and concentration. The collection covers data for the ERS-1, ERS-2 and Envisat missions, and bases on Level 1 data coming from previous reprocessing (ERS REAPER and the Envisat V3.0) but taking into account the improvements made at Level 0/Level 1 in the frame of FDR4ALT (ALT FDR). The Sea Ice TDP provides data from the northern or southern hemisphere in two files corresponding to the Arctic and Antarctic regions respectively for the winter periods only, i.e., October to June for the Arctic, and May to November for the Antarctic. For many aspects, the Sea Ice TDP is very innovative: First time series of sea-ice thickness estimates for ERS Homogeneous calibration, allowing the first Arctic radar freeboard time series from ERS-1 (1991) to CryoSat-2 (2021) Uncertainties estimated along-track with a bottom-up approach based on dominant sources ERS pulse blurring error corrected using literature procedure [Peacock, 2004] The FDR4ALT products are available in NetCDF format. Free standard tools for reading NetCDF data can be used. Information for expert altimetry users is also available in a dedicated NetCDF group within the products. Please consult the FDR4ALT Product User Guide before using the data. The FDR4ALT datasets represent the new reference data for the ERS/Envisat altimetry missions, superseding any previous mission data. Users are strongly encouraged to make use of these datasets for optimal results.

  • Document - Conference Presentation - Poster

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    Remaining-East-West-bias-explained.pdf

    This presentation shows the results obtained from a scientific assessment on the use of GDR-D improved orbit standard and of the consequent improvement in the Sea Surface Height and Sea Level Anomaly Data of altimeter GDR data (A. Ollivier, OSTST 2011).

  • Document - Publication - Paper

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    RA-2-S-Band-anomaly-detection-and-waveforms-reconstruction.pdf

    This paper describes the algorithm developed for the L1b processor that allows to set a flag identifying the data affected by the S-Band anomaly and reconstruct normal echo waveforms.

  • Document - Product Cal/Val Plan/Report

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    RA-2-In-Flight-Instrument-Calibration-and-Level-1b-Verification-Plan.pdf

    This document describes the plan for the RA-2 In-flight Instrument Calibration and Level lb Verification procedures.

  • Document - Technical Note

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    RA-2 S-Band Anomaly Investigation

  • Document - Technical Note

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    RA-2 data Rain Flag

  • Document - Technical Note

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    RA-2 Anomaly of 01-02-2006

  • News - Success Stories

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    Predicting crop yield using Planet data

    The world’s population continues to grow, while the climate crisis is raising Earth’s temperatures and increasing the likelihood of extreme weather events – all of which affect food security.

  • Document - Proceedings

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    PolInSAR-2007-Proceedings-of-the-3rd-International-Workshop-on-Science-and-Applications-of-SAR-Polarimetry-and-Polarimetric-Interferometry.pdf

    Proceedings of PolInSAR 2007 held in Frascati, Italy on from 22-26 January 2007.

  • News - Data Release news

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    PlanetScope and SkySat data now available

    PlanetScope and SkySat missions under evaluation. Interested users can investigate suitability of the data for scientific and R&D activities.

  • News - Data Release news

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    PlanetScope and Skysat data available through ESA’s Third Party Missions Programme

    Through ESA’s Third Party Missions Programme, researchers, scientists and companies from around the world can apply to access Planet’s high-frequency, high-resolution satellite data for non-commercial use.