Vicarious Calibratipon of the DESIS Imaging Spectrometer: Status and Plans

The DLR Earth Sensing Spectrometer (DESIS) on board the International Space Station (ISS) has been providing high quality hyperspectral data to the scientific community and commercial users since the start of operations in September 2018. After almost 4 years in orbit, the DESIS instrument continues to operate correctly and to deliver hyperspectral data products for a wide variety of applications. In order to support this successful activity, the calibration team regularly analyzes the instrument data and provides updates using vicarious calibration. We present here the latest results from the DES IS vicarious calibration and our plans for future improvements

The Spaceborne Imaging Spectrometer DESIS: Mission summary and potential for scientific developments

The DLR Earth Sensing Imaging Spectrometer (DESIS) is a spaceborne instrument installed and operated on the International Space Station (ISS). The German Aerospace Center (DLR) has developed the instrument and the full pre-processing chain up to L2A, while the US company Teledyne Brown Engineering (TBE) provided the Multi-User System for Earth Sensing (MUSES) platform and the infrastructure for operations and data tasking. DESIS is equipped with an on-board calibration unit and a rotating pointing mirror (POI). The POI can change the line of sight in the forward/backward direction (independently of the MUSES orientation), allowing the observation of the same area with different pointing angles within an overflight. About four years after the mission’s kick-off, the DESIS spectrometer was integrated into MUSES in August 2018, marking the start of the commissioning phase. The DESIS on-orbit functional tests were successful, and the DLR-built processing chain installed at DLR for scientific users and at Amazon Web Service for commercial users started to generate operational L1B, L1C and L2A DESIS products. In October 2019 the operational phase started the distribution of the data to scientific and commercial users. Since then, the instrument performance has been constantly evaluated. In a continuous monitoring process, the data quality is controlled and, if necessary, the calibration algorithms and tables are adjusted. This is essential for the later data application by scientists. In particular, the monitoring approaches emphasize the need for high and consistent data quality over long time periods. In autumn 2021, the first DESIS user workshop demonstrated the widespread use of DESIS data for topics like water and terrestrial resource monitoring, biodiversity and forest management. This presentation will give an overview of the DESIS mission, data quality, data access, and provides examples and perspectives on the scientific exploitation of the mission. The contribution for the CHIME mission is presented exemplarily for the CHIME test sites that are constantly observed by DESIS since 2020. DESIS data acquisition opportunities rely on the non-sun-synchronous ISS orbit, resulting in observation and illumination conditions difficult to reproduce. On the other hand, DESIS time series contain images of different day times, sensor incident angles as well as sun zenith angles and thus, can open up new opportunities for the monitoring of Earth system processes that have a daily variability such as photosynthesis. Finally, DESIS multitemporal data stacks can be an essential data base for algorithm and operational processor developments that shall be able to handle massive data amounts. The DESIS data archive is open for such research and developments and thus, is a valuable imaging spectroscopy data source

Data Validation of the DLR Earth Sensing Imaging Spectrometer DESIS

Imaging spectrometry provides densely sampled and finely structured spectral information for each image pixel over large areas, enabling the characterization of materials on the Earth's surface by measuring and analyzing quantitative parameters allowing the user to identify and characterize Earth surface materials such as minerals in rocks and soils, vegetation types and stress indicators, and water constituents. The recently launched DLR Earth Sensing Imaging Spectrometer (DESIS) installed on the International Space Station (ISS) closes the long-term gap of sparsely available spaceborne imaging spectrometry data and will be part of the upcoming fleet of such new instruments in orbit. DESIS measures in the spectral range from 400 and 1000 nm with a spectral sampling distance of 2.55 nm and a Full Width Half Maximum (FWHM) of about 3.5 nm. The various DESIS data products available for users are described with the focus on specific processing steps. A summary of the data quality results are given. The product validation studies show that top-of-atmosphere radiance, geometrically corrected, and bottom-of-atmosphere reflectance products meet the mission requirements

The Spaceborne Imaging Spectrometer DESIS: Data Access and Scientific Applications

The DLR Earth Sensing Imaging Spectrometer (DESIS) is a space-based instrument installed and operated on the International Space Station (ISS). This space mission is the achievement of the collaboration between the German Aerospace Center (DLR) and the US company Teledyne Brown Engineering (TBE). DLR has developed the instrument and the software for data processing, while TBE provides the Multi-User System for Earth Sensing (MUSES) platform, where DESIS is installed, and the infrastructure for operation and data tasking

The genetic architecture of the human cerebral cortex

The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder

THE INFORMATION/ KNOWLEDGE FLOW WITHIN A KNOWLEDGE ORGANIZATION. IT’S ALL ABOUT PEOPLE - A CASE STUDY OF THE GERMAN AEROSPACE CENTER DLR.

The purpose of the paper is to show how DLR plans to organize knowledge along processes and people within its organization. Personal knowledge exchange and information technology are both important and have their own field of application. One important outcome of the analysis is the clear need for transparency of the interfaces, and the chance for the employees to publish their knowledge to other employees easily. An overview of the project named “Establishing an integrated knowledge management system " will be given

BOTTOM-UP! - SOCIAL KNOWLEDGE SHARING IN DLR. A CASE STUDY OF COLLABORATION IN THE GERMAN AEROSPACE CENTER DLR.

Establishing an Integrated Knowledge Management System for the German Aerospace Center (DLR) - a task that is not primarily driven by technology but especially by the way people react and interchange with each other. Not the information technology is the key to a successful knowledge management but the people are. From this follows that the improvement of knowledge processes can be done by bringing the right people together - whether online or offline - to share their knowledge and develop new ideas. Whenever technology is used to enhance these knowledge processes, it has to be in a social way to improve the bottom-up knowledge flow. Our first example is the DLR-Wiki, in which each employee can easily share her or his own knowledge with others inside DLR. The second example is the Knowledge Sharing Meeting, a format of collaboration workshops aiming at creating communities of experts by using a bottom-up approach with the acceptance of executive staff. An overview of the other knowledge management activities at DLR will also be given

The Project is over - The Knowledge is lost? DLR's Project Database

The German Aerospace Centre Center (DLR, Deutsches Zentrum für Luft- und Raumfahrt) reorganized its knowledge management processes with an initiation project called “Establishing an integrated knowledge management system" (EIWis) to close identified critical knowledge gaps. One of the biggest issues was the availability of project data for other project managers during and especially after the project. More than thousand projects are realized in DLR per annum. This means that there is much project knowledge from the past and present which could help to start a new project, to realize it and to achieve success. Lessons Learned from other projects exist somewhere, which can be valuable for a new project. Many project managers work in DLR who could help to solve specific problems in the project realization. Others are experts in their fields, but not easy to identify in a big organization, which has a large variety of research topics. The challenge was to build a network between people, project information and the organization. Approaches to link people and the organization were already part of the EIWis project. Therefore DLR introduced a people’s directory and knowledge sharing workshops. For information sharing, another component of EIWis was very fruitful: the DLR.Wiki. But the Wiki alone was not capable to fulfill the demands of project managers, who need more detailed and structured information about projects. That meant for us that the DLR.Wiki was a solid base for a Project Database, but the final Project Database needed more enhancements. The purpose of the paper is to show how DLR developed its own Project Database according to the needs of project managers and where the advantages and limitations are. Besides, an overview of the Project Database interaction with the other components of the Knowledge Management System will be given