Showing papers by "Peter Reinartz published in 2000"

MOMS - The First Along Track Stereo Camera in Space - A Mission Review

Abstract: MOMS (Modular Optoelectronic Multispectral Stereo Scanner) is a German spaceborne pushbroom scanner for high resolution (HR), multispectral (MS) and threefold along-track stereoscopic imaging. The camera was first flown on the second German Space Shuttle Mission in spring 1993. After the 11 days shuttle mission the camera system was refurbished for a second flight onboard the PRIRODA module of the Russian space station MIR. This mission, called MOMS-2P, lasted from May 1996 to August 1999. MOMS-2P was equipped with a navigation package consisting of a GPS receiver and two redundant gyro subsystems for obtaining position and attitude data with high accuracy. For the MIR orbit altitude of 400 km the ground pixel size was 18 m and 6 m (HR). The orbit inclination was 51.6°. The data takes mainly cover Europe, North-East Africa, Middle East and South America, but also selected image strips from other parts in the world are available. In total approximately 65 Mio. km2 of the land mass have been recorded. In the meantime a series of MOMS data takes have been evaluated. Accuracy analysis using independent ground control led to point accuracies of better than 10 m in X, Y, Z for test sites in Germany. The geometric calibration was conducted by band to band registration for the multispectral channels and by photogrammetric adjustment using precise ground control for the stereo channels (inverse photogrammetry). The paper decribes the imaging technique of the camera, presents the actual status of data recording and data availability, reports on the applied calibration methods and summarises results of photogrammetric data evaluation.

Landslide investigations in southern Kyrgysztan based on a digital elevation model derived from stereoscopic MOMS-2P data

Abstract: In Kyrgyzstan (Central Asia) large landslides are widespread at the eastern rim of the Fergana Basin in an area of active mountain building (Pamir-Tien Shan). Because of the large number of landslides and their difficult accessibility in mountainous terrain the potential of GIS-based analysis of satellite remote sensing data is investigated. This goal requires a spatially and thematically consistent digital database including high resolution digital topographic data as a key element. For this purpose a Digital Elevation Model (DEM) was generated from data of the German multi-line scanner MOMS-2P (Modular Optoelectronic Multispectral Scanner). Processing steps included automated image matching for tie point generation between the 3 stereo strips, photogrammetric block adjustment for reconstructing the exterior and interior orientation of the camera, and finally DEM interpolation. Geodetic GPS measurements were carried out to determine ground control points (GCP) for photogrammetric point determination and independent check points (CP) for assessment of height accuracy of the final DEM. Height accuracy is described by mean and standard deviation of differences between GPS and DEM heights and amounts to 1.1 +/- 17.3m based on 36 CP. In a second step, orthoimages of the 4 MOMS-2P channels were derived. Both MOMS-2P stereo products were analyzed for their suitability investigating landslide phenomena in the Maili-Suu test area. GIS-based analysis including perspective visualizations, surface profiling and derivation of quantitative relief parameters led to topography-based identification of tectonically active elements as one major factor for initiating landslides. The stereo products also allowed detailed analysis of a single landslide. In case of the Kashgarta landslide spatial interference between displaced masses and surrounding stable areas was investigated incorporating geological information. These investigations showed that height accuracy and morphological detail of MOMS-2P stereo products are appropriate for regional satellite remote sensing based analysis of landslide processes in this area.

Ein raumbezogenes Informationssystem für den Wiederaufbau des Kosovo

Abstract: Nach dem Kosovo-Krieg im vergangenen Jahr ist der Wiederaufbau und damit verbunden die langfristige Integration der Balkanregion zu einem zentralen Thema der EU geworden. Neben den sehr zeitkritischen humanitaren Aufgaben sind mittel- und langfristige Planungen durchzufuhren, fur die geographisch exakt zugeordnete Datenbestande von grosem Nutzen sind. Aus diesen Grunden wurde ein Prototyp eines raumbezogenen Informationssystems fur die Unterstutzung des Wiederaufbaus des Kosovo erarbeitet, welches hier vorgestellt wird. Als Grundlage dienen Fernerkundungsdaten fur die thematische Kartierung und die Gewinnung von digitalen Hohenmodellen. Weitere eingesetzte Technologien sind Satellitennavigation fur die Positionierung, Telekommunikation und das Internet fur den Datentransfer. Zusammen mit den durch traditionelle Methoden akquirierten Informationen werden diese Daten in einem Geographischen Informationssystem bearbeitet, abgefragt und visualisiert, so dass sie eine sofort nutzbare Informationsquelle fur Aufbau- und Entscheidungsprozesse darstellen.

Intercalibration of Optical Satellites

Abstract: The homogeneous test site of La Crau (South of France was used for radiometric calibration of the MOMS camera onboard the Russian MIR-Station and of the HRV/HRVIR cameras on the SPOT1 and SPOT4 satellites. The test site has an extension of approx. 400 m x 400 m and is composed of bare soil and pebbles. For the spectral characterization of the test site reflectance measurements with a field spectrometer and a field multichannel radiometer as well as multispectral images from a scanner onboard a low flying aircraft were obtained. To determine atmospheric optical parameters the direct transmission of the atmosphere was measured with sunphotometers and the ground spectrometer simultaneously with the overpass of the space cameras. With the measured reflectances and atmospheric parameters, the Modtran 3.5 [1] and 6S [10] radiative transfer codes were used to calculate the spectral radiance reaching the space cameras. The paper describes the measuring The homogeneous test site of La Crau (South of France) was used for radiometric calibration of the MOMS camera onboard the Russian MIR-Station and of the HRV/HRVIR cameras on the SPOT1 and SPOT4 satellites. The test site has an extension of approx. 400 m x 400 m and is composed of bare soil and pebbles. For the spectral characterization of the test site reflectance measurements with a field spectrometer and a field multichannel radiometer as well as multispectral images from a scanner onboard a low flying aircraft were obtained. To determine atmospheric optical parameters the direct transmission of the atmosphere was measured with sunphotometers and the ground spectrometer simultaneously with the overpass of the space cameras. With the measured reflectances and atmospheric parameters, the Modtran 3.5 [1]and 6S [10] radiative transfer codes were used to calculate the spectral radiance reaching the space cameras. The paper describes the measuring techniques and discusses the calibration results.

Radiometric intercalibration of MOMS and SPOT by vicarious method

Abstract: The homogeneous test site of La Crau (South of France) was used for radiometric calibration of the MOMS-camera onboard the Russian MIR-Station and of the HRV/HRVIR cameras on the SPOT-01 and SPOT-04 satellites. The test site has an extention of approx. 400 m x 400 m and is composed of bare soil and pebbles. For the spectral characterisation of the test site reflectance measurements with field spectrometers as well as multispectral images with airborne instruments from low flight altitude were obtained. To determine atmospheric optical parameters the ground irradiance of the sun was measured during the time the space cameras passed over the test site. With the measured reflectances and atmospheric parameters the 6S-radiation transfer model was used to calculate the spectral radiance reaching the space cameras. The paper describes the measuring techniques and discusses the calibration results.