Polar Satellite Launch Vehicle (PSLV) C37 & Cartosat-2

The Indian Space Research Organisation (ISRO) successfully launched a record 104 satellites in one mission from Sriharikota on 15th February, 2017 by relying on its workhorse Polar Satellite Launch Vehicle (PSLV) C37 rocket. 

• An earth observation Cartosat-2 series satellite (Cartosat 2 D) and two other Indian Nano Satellites (INS) were the only Indian satellites launched.
• The remaining were from the United States, Israel, the UAE, the Netherlands, Kazakhstan and Switzerland.
• Of the 101 foreign satellites launched, 96 were from the U.S. and one each from the other five countries.
• Till now Russia held the record of launching 37 satellites in a single mission, in 2014, while the National Aeronautics and Space Administration (NASA) of the U.S. launched 29 satellites in one go in 2013.
• The launch is particularly significant as ISRO now cements its position as a key player in the lucrative commercial space launch market by providing a cheaper yet highly reliable alternative.

Cartosat 2 Series:-

• The Cartosat 2 D satelite launched with the PSLV 37 C on 15 February 2017 is the fifth among the six satelites in the series.
• The previous Cartosat-2 C satellite was the primary satellite carried by PSLV-C34 in July 2016. This satellite is similar to the earlier Cartosat-2, 2A and 2B.
• Cartosat-2 suffered from some problems after launch in the year 2007. An improved Cartosat 2A was launched in 2008. Cartosat 2B followed in 2010.
  • Beginning with Cartosat 2C, a Multi-spectral camera was added and a lower 505 km orbit for better ground resolution was introduced.
  • Cartosat 2C was launched in June 2016.
  • Cartosat 2D has been launched on 15th February 2017 and Cartosat 2E is planned for late 2017.
• Cartosat-2 is an advanced remote sensing satellite with a single panchromatic camera (PAN) capable of providing scene-specific spot images for cartographic applications.
• The camera is designed to provide images with better than one meter spatial resolution and a swath of 10 km.
• The satellite will have high agility with capability to steer along and across the track up to + 45 degrees.
• It is to be placed in a sun-synchronous polar orbit.
• It will have a revisit period of approximately four days. The re-visit can be improved to one day with suitable orbit manoeuvres.
• Several new technologies like two mirror on axis single camera, Carbon Fabric Reinforced Plastic based electro optic structure, lightweight, large size mirrors, JPEG like data compression, advanced solid state recorder, high-torque reaction wheels and high performance star sensors are being employed in Cartosat-2.

• The imagery of Cartosat-2 series satellite will be useful cartographic applications, urban and rural applications, coastal land use and regulation, utility management like road network monitoring, water distribution, creation of land use maps, precision study, change detection to bring out geographical and man made features and various other Land Information System (LIS) and Geographical Information System (GIS) applications. 

Polar Sun Synchronous Orbit:-

• This orbit is a special case of the polar orbit.
• Like a polar orbit, the satellite travels from the north to the south poles as the Earth turns below it.
• In a sun-synchronous orbit, though, the satellite passes over the same part of the Earth at roughly the same local time each day.
• This can make communication and various forms of data collection very convenient.
• Approximate distance of the orbit is from 500 to 600 km.

ISRO nano satellites (INS):- 

• Besides setting the record for the most number of satellites launched in a single mission, the Indian space agency has launched two nano satellites weighing less than 10 kg with the PSLV C37 mission.
• It is a technology demonstrator for a new class of satellites called ISRO nano satellites (INS).
• The main objective of the INS, which will be launched together with bigger satellites, is to provide a platform on which payloads up to 5 kg from universities and R&D laboratories, and ISRO itself can be easily integrated for carrying out scientific research activities.
• With many Indian universities already building and launching nano satellites, the availability of a dedicated nano satellites platform is sure to boost space research in India.