Model Answer
0 min readIntroduction
India’s space program has significantly bolstered its capabilities in Earth observation, crucial for both civilian and strategic applications. Cartosat-3 and RISAT-2B represent the latest generation of Indian remote sensing satellites, building upon the successes of their predecessors. Cartosat-3, launched in November 2019, is a high-resolution Earth observation satellite, while RISAT-2B, launched in May 2019, is a radar imaging satellite. Both satellites offer substantial improvements in resolution, coverage, and operational capabilities, enhancing India’s ability to monitor its borders, infrastructure, and natural resources. This answer will discuss the salient features of these satellites and how they surpass their earlier versions.
Cartosat-3: A High-Resolution Eye in the Sky
Cartosat-3 is a third-generation, advanced imaging satellite in the Cartosat series. It is designed to provide high-resolution, panchromatic and multispectral imagery.
- Resolution: Its key feature is its sub-meter resolution (0.8m), significantly higher than the 1-meter resolution of Cartosat-2 series satellites. This allows for detailed mapping and analysis.
- Swath Width: It has a wider swath width compared to its predecessors, enabling larger area coverage in a single pass.
- Applications: Cartosat-3 imagery is used for urban planning, rural resource management, disaster management, infrastructure monitoring, and coastal and inland waterway mapping.
- Instrumentation: It carries a panchromatic camera and three multispectral cameras.
RISAT-2B: All-Weather Surveillance
RISAT-2B is a radar imaging satellite, meaning it can acquire images regardless of cloud cover or daylight. This is a significant advantage over optical satellites like Cartosat-3.
- Radar Technology: It utilizes Synthetic Aperture Radar (SAR) technology, which transmits microwave signals and analyzes the reflected signals to create images.
- Resolution: RISAT-2B offers a resolution of 3.98 meters, an improvement over the 5-meter resolution of RISAT-1.
- Applications: RISAT-2B is primarily used for all-weather surveillance, monitoring borders, tracking ships, and providing data for disaster management.
- Frequency Band: Operates in the X-band frequency.
Comparison with Predecessors
The following table highlights the key differences between Cartosat-3/RISAT-2B and their predecessors:
| Feature | Cartosat-2 Series | Cartosat-3 | RISAT-1 | RISAT-2B |
|---|---|---|---|---|
| Resolution | 1 meter | 0.8 meters | 5 meters | 3.98 meters |
| Imaging Type | Optical | Optical | Radar (SAR) | Radar (SAR) |
| All-Weather Capability | No | No | Yes | Yes |
| Swath Width | 9.84 km | Wider than Cartosat-2 | N/A | N/A |
| Primary Application | Mapping, Urban Planning | High-Resolution Mapping, Infrastructure Monitoring | Border Surveillance, Disaster Management | All-Weather Surveillance, Maritime Monitoring |
Superiority of Newer Satellites
Cartosat-3 and RISAT-2B represent a significant leap forward due to several factors:
- Enhanced Resolution: The improved resolution allows for more detailed analysis and identification of objects on the ground.
- Increased Frequency of Revisits: The combination of multiple satellites in orbit (including Cartosat-3 and RISAT-2B) allows for more frequent revisits to the same area, providing timely data for monitoring dynamic events.
- All-Weather Capability (RISAT-2B): The ability to acquire images regardless of weather conditions is crucial for continuous monitoring, especially in regions prone to cloud cover.
- Improved Data Processing: Advancements in data processing algorithms and infrastructure enable faster and more accurate analysis of satellite imagery.
- Strategic Implications: These satellites enhance India’s self-reliance in acquiring critical geospatial data, reducing dependence on foreign sources.
The data from these satellites is used by various agencies including the Indian Space Research Organisation (ISRO), the Ministry of Defence, and the National Disaster Management Authority (NDMA).
Conclusion
Cartosat-3 and RISAT-2B represent a substantial advancement in India’s Earth observation capabilities. Their superior resolution, all-weather functionality, and increased revisit frequency provide a significant advantage over their predecessors. These satellites are vital for a wide range of applications, from civilian mapping and disaster management to strategic surveillance and border security. Continued investment in space-based assets like these is crucial for India’s economic development and national security, solidifying its position as a leading space power.
Answer Length
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