RASAT Earth Observation Satellite

RASAT is the first Earth observation satellite developed entirely with national capabilities by TÜBİTAK Space Technologies Research Institute (UZAY). The satellite is associated with Türkiye’s objectives of moving independently in space research and reducing external dependency.

RASAT was launched into space on 17 August 2011 aboard a Dnepr launch vehicle from Russia’s Yasny Launch Base and successfully entered a Sun-synchronous orbit at an altitude of 687 km 969 seconds after launch. Although its design life was projected at three years, the satellite operated continuously for ten years.

Development Process

Türkiye’s first remote sensing satellite, BİLSAT-1, was developed in collaboration between TÜBİTAK UZAY and British Surrey Satellite Technology Limited (SSTL) and launched in 2003. This satellite provided Türkiye with its first experience in satellite technology but employed a foreign-partnered technology transfer model during production. RASAT, developed after this experience, is Türkiye’s second remote sensing satellite but the first indigenous Earth observation satellite. No external consultancy or technical support was used in its production; both software and hardware were developed entirely by TÜBİTAK UZAY engineers.

Technical Characteristics and Capacity

RASAT, weighing approximately 93 kg, operated in a Sun-synchronous orbit. Its main technical specifications are as follows:

• Resolution: 7.5 m panchromatic (black and white) and 15 m multispectral (RGB)
• Frame size: 30 × 30 km
• Imaging capacity: 33 frames per pass (960 km long swath)
• Total archive: 13,362 images from 5,284 acquisitions (covering approximately 12 million km²)

During its mission, the satellite completed 58,726 orbits and established communication with ground stations 22,203 times.

Image of Istanbul captured by RASAT (TÜBİTAK SPACE)

Ground Stations and Gezgin Portal

During the operation of RASAT, the ground station at TÜBİTAK UZAY in Ankara was used for testing, software uploads, and image downloads. During the commissioning phase, a temporary ground station in Norway was also utilized. The acquired images were made accessible through Gezgin, Türkiye’s first satellite image portal.

Image of Türkiye captured by RASAT (Traveler)

Thanks to its integration with e-Devlet, Gezgin provided free services to academic, public sector, and private sector users. RASAT images were widely used in the following areas:

• Monitoring urban development and city planning
• Land use and agricultural productivity analysis
• Monitoring water levels in dams
• Evaluation of environmental changes and natural disasters (e.g., floods, earthquakes)
• Detection of oil spills in seas