TanDEM-X

TanDEM-X
Mission type	Radar Imaging
Operator	DLR
COSPAR ID	2010-030A
SATCAT no.	36605
Website	Home
Mission duration	Elapsed: 14 years and 18 days
Spacecraft properties
Manufacturer	EADS Astrium Satellites
Start of mission
Launch date	21 June 2010, 02:14:00 (2010-06-21UTC02:14Z) UTC
Rocket	Dnepr
Launch site	Baikonur 109/95
Orbital parameters
Reference system	Geocentric
Regime	Low Earth

TanDEM-X (TerraSAR-X add-on for Digital Elevation Measurement) is the name of TerraSAR-X's twin satellite, a German Earth observation satellite using SAR (Synthetic Aperture Radar) - a modern radar imaging technology. Implemented in a Public-Private-Partnership between the German Aerospace centre (DLR) and EADS Astrium (now Airbus Defence and Space), it is a second, almost identical spacecraft to TerraSAR-X (TSX). TanDEM-X (TDX) is also the name of the satellite mission flying the two satellites in a closely controlled formation with typical distances between 250 and 500 m.^[1] The twin satellite constellation allowed the generation of WorldDEM global digital elevation models starting in 2014.

Mission

The primary mission objective is the generation of WorldDEM, a consistent global Digital Elevation Model (DEM) with an unprecedented accuracy according to better than DTED Level 2 specifications. WorldDEM resolution will correspond to DTED Level 3 (post spacing of better than 12 meters) and a height accuracy of better than 2m (relative)- a standard not yet defined. Digital Elevation Models of posting better than DTED Level 2 are often called HRTI (High Resolution Terrain Information) DEM.^[1]

WorldDEM

WorldDEM is a highly accurate, detailed and consistent DEM of the Earth's entire land surface, acquired and generated within three years after launch. Available from 2014, WorldDEM is to feature a vertical accuracy of 2m (relative) and 4m (absolute), within a horizontal raster of approximately 12x12 square meters, slightly varying depending on the geographic latitude. Infoterra GmbH, a 100% subsidiary of Astrium, holds the exclusive commercial marketing rights for the WorldDEM and is responsible for the adaptation of the elevation model to the needs of commercial users worldwide. When the system launched, accuracy over forested areas was unknown.^{[citation needed]}

First 3D Image

Researchers at the German Aerospace Center facility in Oberpfaffenhofen published the first 3D images from the TanDEM-X satellite mission. A group of Russian islands of the Severnaya Zemlya group in the Arctic Ocean was selected for the first test.^[2]