Support

Overview of the Portal

The Luxembourg Space Agency (LSA) Data Center is the Luxembourg entry point to data products of the Copernicus Sentinel constellation.
In particular, LSA Data Center gives access to Sentinel 2 data. Access to Sentinel 1 data is under consideration.
The LSA Data Center allows the users to search, discover and download the data. To this purpose all the data are referenced and indexed in a real time updated geo-catalogue. The catalogue allows the users to query the archive on the basis of specific criteria such as product type, orbit or cloud coverage and to select the needed products for the download. Two levels of services are offered for normal and premium users.
The LSA Data Center is particularly intended to provide a privileged access to Luxembourg users.

Landing Page

The collgs.lu landing page provides easy access to all parts of LSA Data Center.
The "Account" tab of the menu provides the possibility to "Register" or to "Login" if you are already registered on collgs.lu.
You can also find further information "About" LSA Data Center.

Catalogue Client

Overview

The LSA Data Center Catalogue Client provides an enhanced solution to discover, view, and download available Earth Observation data (EO data). These are primarily Sentinel 2 data sets. Sentinel-1 will follow soon.

Timeslider

The timeslider presents the distribution and number of (different) datasets in time (bar graphs). You can make a temporal selection on the timeslider:

  • panning (only in the bottom area): left click + drag or one finger drag or plus and minus icons in the middle
  • zooming: mouse wheel scroll or two finger pinch or right and left arrow icons
  • reloading timeslider: spinner icon in the middle
  • selecting a time interval for product searching and viewing (only in the upper area): left click + drag or one finger drag or click on histogram bucket
  • showing number of total available products in histogram bucket: hover over histogram bucket
  • showing start and end of current selection: click + hold on selection (or look at time filter)

Interactive tutorial

When the Catalogue Client is opened the first time a short interactive tutorial starts guiding you through the main features and elements of the Catalogue Client. You can start this short intro anytime clicking the button on the lower right of the window.

The Catalogue Client appears at first in about the following view:

This view is for Visualisation and browse through existing image data in the map window. You can now zoom-in and pan the data. You can see a grid on the right part of the map. These are the appr. scene extents/foot prints without image content. When you start zooming-in the satellite images will appear in a reduced resolution natural colour presentation for viewing but will show full resolution when zooming in to full resolution. The map windows loads / selects data for the shown extent in the background. The time filter can changed using left click and drag in the upper area of the timeslider at the bottom of the map window or clicking on a histogram bucket.

Satellite scenes in the map window are used for a preview (pre-selection) for the download (see Download below). If you change the map extent or zoom in and out the pre-selection changes, too.

There are two panels: the left menu for selections, filters and background layers and on the right for presenting selcted data and downloads (further details: see below).

If you are hovering over the footprints (grey rectangles) or the single buckets in the timeslider the respective scene is highlighted in the map, timeslider and the selection menu at the right.

Product selection

If you use the button in the upper right part of the map window the menu/window with search results appears. Now the Catalogue Client is in the download modus, where you can search, select and download of check the satellite scenes.

LSA Data Center provides you with Viewing functionalities in the map window and Filter/Search functionality for download in a single tool ("new usage paradigm"):

Filter

There are two possibilities to query data in the Catalogue-Client. At the left there is the Filter window - see figure below:

1. You can apply a temporal query --> "Time Filter": Enter Start and End date of your search interval.

2. You can apply a spatial query: --> "Spatial Filter": using the "Rectangle" or "Polygon" drawing options under "Draw"

Additional Filters

Additional Filters can be applied on the available information stored with the data sets. Filters can be applied to optical featrues, such as the Cloud Cover.

Layers

If you click on "Layers" the "Overlay", "Layer" and "Base Layer" legend can be seen. The "Base Layer " is the background for the map window for orientation and the "Layer" presents the selected data sets and its products or products levels (e.g. Sentinel-2). You can select and change the order of the layers.

Remark: The order of of the layers has an influence on the order of layers in the timeslider (see below).

Save search query

Clicking on the button next to the level in the search result tab, it is possible to save the search query. To download the XML file click with the right mouse button on the link and then "Save Link As...".

User Management

The LSA Data Center platform makes use of a User Management System (UMS), which is used for the authentication and authorisation of users. The UMS is used to manage users, user groups and user rights. Some changes of group membership and user rights can't be done automatically, but must be authorised and granted according to the LSA Data Center Governance (Rules for user groups and their access rights). The process of granting additional user rights to an user can last some time.

The main advantage of the UMS is that it provides a single-sign-on (SSO) procedure, which means that only a single login (after registration) is required by the user to access the configured and integrated LSA Data Center services.

Login

You can log in over the login block of the "Account" tab of the Portal which is shown in the figure below.

Once you have pressed the "Login" button you are redirected to the CAS login form. After entering your credentials and submitting the form you are logged in on the LSA Data Center platform...

Registration Form

If you don't have an account yet, you can create one by clicking on the "register" link next to the login block. This is necessary before you can login as a LSA Data Center user.

You will be redirected to a self-registration form which is shown in the figure below. You have to accept the LSA Data Center Terms and Conditions and Privacy Statement during registration.

After sending the completed form you will be redirected to the LSA Data Center Portal.

Further questions

If you have any further technical question, please feel free to contact the LSA Data Center Helpdesk:





Sentinel 2

Sentinel-2 is an Earth observation mission developed by ESA as part of the Copernicus program to provide continuity of SPOT and LANDSAT-type image data, contribute to ongoing multispectral observations and benefit Copernicus services and applications such as land management, agriculture and forestry, disaster control, humanitarian relief operations, risk mapping and security concerns. The mission comprises a constellation of two identical polar-orbiting satellites (Sentinel-2A and Sentinel-2B) placed in the same orbit, phased at 180° to each other. Sentinel-2A was launched on 23 June 2015 and Sentinel-2B followed on 7 March 2017.

Both satellites carry an innovative wide swath high-resolution multispectral imager with 13 spectral bands that combines a high spatial resolution (up to 10 x 10 m) with novel spectral capabilities and high revisit times (5 days at the equator and 2.3 days at mid-latitudes with both satellites, respectively).

For more information please refer to ESA's mission description that can be found here: https://sentinel.esa.int/web/sentinel/missions


Data products:

The Sentinel-2 multispectral imager (MSI) undertakes systematic acquisition in a single observation mode. The Sentinel-2 data products available for users are listed in the following figure: Sentinel-2 available products

Level-1C: Top of atmosphere reflectances in fixed cartographic geometry (combined UTM projection and WGS84 ellipsoid). Level-1C images are a set of tiles of 100 km², each of which is approximately 600 MB in size. These products contain applied radiometric and geometric corrections (including orthorectification and spatial registration).

Level-2A: Bottom of atmosphere reflectances in cartographic geometry. The Level-2A operational processor generates, from algorithms of scene classification and atmospheric correction, Level-2A (BOA reflectance) products based on Level-1C products. In addition to the operational processor, Level-2A data products can be generated by the user by on the user side by using a processor running on ESA's Sentinel-2 Toolbox, such as ESA SNAP (http://step.esa.int/main/toolboxes/snap/). The Level-2A is available since March 2017 as pilot version (Level-2Ap) and since 26 March 2018 as operational version. In the geocatalog the two version are published in the same layer.


Sentinel-2 Mission Overview

https://sentinel.esa.int/web/sentinel/missions/sentinel-2

File format of measurement data: JPEG2000

Suggested software: ESA SNAP/Sentinel Toolbox (http://step.esa.int/main/download/)

Sentinel-2 acquisition plans:

https://sentinels.copernicus.eu/web/sentinel/missions/sentinel-2/acquisi...

Sentinel-2 Level-1C Processing Overview

https://earth.esa.int/web/sentinel/technical-guides/sentinel-2-msi/level...

Sentinel-2 Level-1C spatial resolution

https://sentinels.copernicus.eu/web/sentinel/user-guides/sentinel-2-msi/...

Sentinel-2 Level-1C radiometric resolution and band numbering

https://sentinels.copernicus.eu/web/sentinel/user-guides/sentinel-2-msi/...

Sentinel-2 Level-2A Processing Overview

https://earth.esa.int/web/sentinel/technical-guides/sentinel-2-msi/level...


Terms and conditions

https://scihub.copernicus.eu/twiki/pub/SciHubWebPortal/TermsConditions/T...

Further questions

If you have any further questions regarding the Sentinel products, please feel free to contact the thematic Helpdesk: