We focus on the world coverage Shuttle Radar Topography Mission XSAR data. And will be introducing more and more European and Asian data sets as well as good African and South American coverages. With the help of the international mapping communities, we hope to offer higher state by state and county by country data sets.
The Shuttle Radar Topography Mission (SRTM) is an international research effort that obtained digital elevation models on a near-global scale from 56° S to 60° N, to generate the most complete high-resolution digital topographic database of Earth prior to the release of the ASTER GDEM in 2009. SRTM consisted of a specially modified radar system that flew on board the Space Shuttle Endeavour during the 11-day STS-99 mission in February 2000, based on the older Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar (SIR-C/X-SAR), previously used on the Shuttle in 1994. To acquire topographic (elevation) data, the SRTM payload was outfitted with two radar antennas. One antenna was located in the Shuttle's payload bay, the other – a critical change from the SIR-C/X-SAR, allowing single-pass interferometry – on the end of a 60-meter (200-foot) mast that extended from the payload bay once the Shuttle was in space. The technique employed is known as Interferometric Synthetic Aperture Radar.
The elevation models are arranged into tiles, each covering one degree of latitude and one degree of longitude, named according to their south western corners. It follows that "n45e006" stretches from 45°N 6°E to 46°N 7°E and "s45w006" from 45°S 6°W to 44°S 5°W. The resolution of the cells of the source data is one arc second, but 1" (approx. 30 meter) data have only been released over United States territory; for the rest of the world, only three-arc-second (approx. 90-meter) data are available. Each one arc second tile has 3,601 rows, each consisting of 3,601 16 bit bigendian cells. The dimensions of the three-arc-second tiles are 1201 x 1201.
The elevation models derived from the SRTM data are used in Geographic Information Systems. They can be downloaded freely over the Internet, and their file format (.hgt) is supported by several software developments.
The Shuttle Radar Topography Mission is an international project spearheaded by the U.S. National Geospatial-Intelligence Agency (NGA) and the U.S. National Aeronautics and Space Administration (NASA).
Volgograd Arena (45,000 spectators): An emotional World Cup venue. On the bank of the Volga, the new stadium was built against the backdrop of the war memorial "Mother's Homeland Calls". During construction, bones were found by soldiers of the Second World War.
Group matches: Tunisia - England (June 18); Nigeria - Iceland (22 June); Saudi Arabia - Egypt (25 June); Japan - Poland (June 28)
Mordovia Arena (45,000 spectators): On the outskirts of Saransk, the new building was launched in 2010, the 1000th anniversary of the unification of the Mordovian and Russian population. After the World Cup there will be a dismantling for tennis and volleyball fields.
Group matches: Peru - Denmark (16 June); Colombia - Japan (19 June); Iran - Portugal (25 June); Panama - Tunisia (June 28)
Samara Arena (45,000 spectators): The ambitious construction project in the forest just outside the city lagged behind the schedule for a long time.
Group matches: Costa Rica - Serbia (17 June); Denmark - Australia (21 June); Uruguay - Russia (25 June); Senegal - Colombia (June 28)
A knockout round, a quarter-finals | Source: REUTERS
Rostov on the Don-Arena (45,000 spectators): Right on the banks of the Don is the new arena. The roof of the new building should symbolize the course of the river. FK Rostov, who beat the Bavarians in the Champions League, is playing here after the World Cup.
Group matches: Brazil - Switzerland (17 June); Uruguay - Saudi Arabia (June 20); South Korea - Mexico (23 June); Iceland - Croatia (June 26th)
A knockout round | Source: REUTERS