Context

An ISRO GSLV-II rocket will launch the GISAT-1 mission. 

About:

• GISAT-1 is an Indian earth observation satellite to be launched in geostationary orbit. It is tasked with continuous observation of Indian sub-continent and quick monitoring of natural hazards and disaster.
• GISAT carries an imaging payload consisting of multi-spectral, multi-resolution from 50 m to 1.5 km.
• It will operate in geostationary orbit above the Southern India region after being launched from Sriharikota, India.
• The rocket consists of three stages and four liquid engine strap-on rocket motors that use UDMH and N2O4.
  • First Stage: The solid propellant first stage uses Hydroxyl-terminated polybutadiene (HTBP) and has a burn time of around 100 seconds.
    • It is important to keep in mind that once a solid motor is ignited, there is no shutting it off.
  • Second Stage: Also used by the second stage, Unsymmetrical dimethylhydrazine (UDMH) is the fuel of choice which has been used since the 1950s by many rocket companies, and Nitrogen tetroxide (N2O4) is the oxidizer of choice.
  • Third Stage: Finally, the third stage uses more familiar and frequently used propellants, Liquid Oxygen (LOX) as the oxidizer and Liquid Hydrogen (LH2) as the fuel.
• Using all the energy from these stages combined, ISRO can launch up to 2500 kg to Geostationary Transfer Orbit (GTO).

Specification:

What is GSLV Mk II?

• Geosynchronous Satellite Launch Vehicle Mark-II (GSLV Mk II) is the largest launch vehicle developed by India, which is currently in operation.
• This fourth-generation launch vehicle is a three-stage vehicle with four liquid strap-ons.
• The indigenously developed cryogenic Upper Stage (CUS), which is flight-proven, forms the third stage of GSLV Mk II.
• From January 2014, the vehicle has achieved four consecutive successes.

Significance of the mission:

• Informative pictures: It will provide pictures of the area of interest on a near real-time basis including border areas.
  • GISAT will provide near real-time pictures of large areas of the country, under cloud-free conditions, at frequent intervals.
  • That is, selected Sector-wise image every 5 minutes and entire Indian landmass image every 30 minutes at 50 m spatial resolution.
• Security: With GISAT-1, the government can keep a constant watch on borders.
• Monitoring geographic changes: Furthermore, it can monitor any change in the geographical condition of the country.