In early 2009 the entire archive of the American Landsat remote sensing program will be available for free and on-line. Last April, the US Geological Survey (USGS) – the Landsat system Operator – announced that access to the archive of Landsat images will become free. Secretary of the Interior, Dirk Kempthorne, speaking at the ESRI UC Senior Executive Summit in San Diego, announced that the 35 years of archived Landsat data will be made available over the web free to the public by the end of the year. The EROS Data Center (EDC) of the USGS will be the lead centre to implement this initiative.
According to the staged project implementation, free public access to Landsat 7 imagery data is open as of October, including new images. Scenes with cloud cover less than 20% after automatic processing are ready for downloading via interface programs EarthExplorer and Glovis with minimum time delay following the acquisition.
In December users will be able to work with Landsat 5 images (TM sensor), in January 2009 – with Landsat 4 (TM sensor) and Landsat 1-5 (MSS sensor) imagery. The Thematic Mapper (ТМ) – is the optical mechanical scanner, providing imaging at 30 m resolution in six bands of the visible, NIR and mid-infrared spectrum and at 120 m in long-wave IR band. In its turn the Multispectral Scanner (MSS) enables the receipt of images with 80 m of spatial resolution.
Landsat-1, launched back in 1972, became the first civil satellite ensuring operational transmission of middle resolution imagery via radio link. Today two Landsat satellites – Landsat-5 and -7 are still in orbit and operating. However, due to its age, Landsat-5 satellite, launched in 1984, has a limited use. Landsat-7 images have defects due to malfunctioning in ETM+ sensor operations. The launch of the new Landsat-8 satellite (LDCM project – Landsat Data Continuity Mission) is scheduled for year 2011.
Earlier Brazil and China had implemented free distribution of CBERS program imagery via Internet. Now the list of available programs will be expanded by Landsat.