ISRO successfully launches 'spy satellite' RISAT 1

After Agni V, India successfully launched its own spy satellite RISAT-1 on April 26, 2012 morning from Sriharikota. RISAT-1 
9Radar Imaging Satellite) can deliver crystal clear pictures in all weather conditions.

The indigenous RISAT-1 - which stands for Radar Imaging Satellite - has a lifespan of five years and will be used for disaster prediction and agriculture forestry. RISAT's high resolution pictures and microwave imaging could also be used for defence purposes.

India now joins Japan, Europe, Canada and Israel to boast of such technology. Weighing at 1528 Kg, RISAT-1 is the heaviest satellite ever launched by India. The total cost of the project was around Rs 500 crore.

For ISRO, this is the first launch this fiscal as well as in the calendar year. Remote sensing satellites send back pictures and other data for use. India has the largest constellation of remote sensing satellites in the world providing imagery in a variety of spatial resolutions, from more than a metre ranging up to 500 metres, and is a major player in vending such data in the global market. 

With 11 remote sensing/earth observation satellites orbiting in the space, India is a world leader in the remote sensing data market. The 11 satellites are TES, Resourcesat-1, Cartosat-1, 2, 2A and 2B, IMS-1, Risat-2, Oceansat-2, Resourcesat-2 and Megha-Tropiques. 

Risat-1's synthetic aperture radar (SAR) can acquire data in C-band and would orbit the earth 14 times a day. In 2009, ISRO had launched 300 kg Risat-2 with an Israeli built SAR enabling earth observation in all weather, day and night conditions. 

With this launch the PSLV rocket has launched successfully 53 satellites out of 54 it carried - majorly remote sensing/earth observation satellites both Indian and foreign - and has been a major revenue earner for ISRO. 

The one failure happened in 1993 when the satellite was not able reach the orbit. The rocket that delivered RISAT-1 in the space is ISRO's four stage PSLV's upgraded variant called PSLV-XL. 

The letters XL stand for extra large as the six strap-on motors hugging the rocket at the bottom can carry 12 tonnes of solid fuel as against the base version that has a fuel capacity of nine tonnes. 

The PSLV's four stages are fuelled with solid and liquid propellants. The first and third stages are fuelled by solid fuel while the second and fourth stages are powered by liquid fuel. 

ISRO had used the PSLV-XL variant for its Chandrayaan-1 moon mission in 2008 and for launching the GSAT-12 communications satellite in 2011.

Titbits of RISAT-1

• Ø India successfully launched its own 'spy satellite' RISAT-1. The Polar Satellite Launch Vehicle (PSLV) carrying the indigenous radar imaging satellite lifted off from Sriharikota spaceport at 5.47 am on April 26, 2012.
• Ø RISAT-1 is India's heaviest satellite till date. It weighs 1528 kilograms. It has day and night viewing capability and will be able to see through cloud cover.
• Ø The satellite's main purpose will be to monitor crops and forecast floods during the Kharif season, according to ISRO.
• Ø The total cost of the mission is about Rs. 500 crore. It is probably the most expensive and most complex mission to be launched from India till date.
• Ø The all-weather surveillance tool is sometimes referred in common parlance as a spy satellite.
• Ø Indian Space Research Organisation (ISRO) chairman Dr K Radhakrishnan declared the mission "a grand success".

About RISAT:-

• After the November 26, 2008 Mumbai attacks, the launch plan was modified to launch RISAT-2 before RISAT-1. since the indigenous C-band SAR to be used for RISAT-1 was not ready. RISAT-1 used an Israel Aerospace Industries (IAI) X-band SAR sensor.  
• RISAT-2 was the first of the RISAT series to reach orbit. It was launched successfully on April 20, 2009 by a PSLV rocket. The 300-kg satellite was built by ISRO using a X-band SAR manufactured by IAI.
• RISAT-1 is an indigenously developed radar imaging satellite expected to be launched by a PSLV rocket by January 2012. RISAT-1 was postponed in order to prioritize the building and launch of RISAT-2.