## 5 Future directions of remote sensing  
The advances made in spaceborne remote sensing in the last 50 years, from sputnik 1 to Worldview-1, has been phenomenal. The present trends point to increasing several innovations. First, availability of data from multiple sensors with wide array of spatial, spectral, and radiometric characteristics. These data will be available from multiple sources. Second, significant advances have been made in harmonizing and synthesizing data from multiple sources that facilitates the use of data from these sensors of widely differing characteristics and sources. We also expect vendors to market data from multiple sources by harmonizing and by adding value. Third, availability of data from a constellation such as from Rapidgee at very high resolution of 6.5 meter, in five bands including a red-edge band, and with ability to cover the entire world in 13-day frequency is a likely attractive form of  
Figure 13: WRSI anomaly as of the 2\({}^{\text{nd}}\) dekad of March, 2007 for the same southern Africa region.  
data collection. This will certainly require innovations in data handling, storage, and backup. But for applications, a combination of very high spatial resolution and frequent coverage is very attractive. Fourth, the micro satellites that specialize in gathering data for specific geographic location and/or for particular applications are likely to become more attractive. Fifth, for many environmental and natural resource applications global wall-to-wall coverage is essential and here satellites like Landsat will continue to play most important role. Sixth, data availability in hyperspectral and hyperspatial sensors brings in new challenges in data mining, processing, backup, and retrieval. Seventh, the advances made in data synthesis, presentation, and accessibility through systems such as Google Earth will bring in new users and multiply applications of remote sensing in environmental sciences and natural resources management.  
The authors expect that the future needs of the spatial data will be met overwhelmingly by spaceborne remote sensing.  
**Acronyms and Abbreviations**  
ASTER Advanced Space borne Thermal Emission and Reflection Radiometer  
ALI Advanced Land Imager  
AVHRR Advanced Very High Resolution Radiometer  
CBERS -2 China-Brazil Earth Resources Satellite  
FORMOSAT Taiwanis Satellite Operated by Taiwanis National Space Organization NSPO. Data  
Marketed by SPOT  
Hyperion First Spaceborne Hyperspectral Sensor Onboard Earth Observing-1(EO-1)  
IKONOS High-Resolution Satellite Operated by GeoEye  
IRS-1C/D-LISS Indian Remote Sensing Satellite/Linear Imaging Self Scanner  
IRS-P6-AWiFS Indian Remote Sensing Satellite/Advanced Wide Field Sensor  
KOMFOSAT Korean Multipurpose Satellite. Data Marketed by SPOT Image  
Landsat-1, 2, 3 MSS Multi Spectral Scanner  
Landsat-4, 5 TM Thematic Mapper  
Landsat-7 ETM+ Enhanced Thematic Mapper Plus  
MODIS Moderate Imaging Spectral Radio Meter  
QUICKBIRD Satellite from DigitalGlobe, a private company in USA  
RAPID EYE - A/E Satellite constellation from Rapideye, a German company  
RESOURSESAT Satellite launched by the India  
SPOT Satellites Pour l'Observation de la Terre or Earth-observing Satellites  
SWIR Short Wave Infrared Sensor  
VNIR Visible Near-Infrared Sensor  
WORLDVIEW