GISAT 1, 1A (EOS 03, 05)

GISAT 1 [ISRO]

GISAT 1 (GEO Imaging Satellite) is an Indian earth observing satellite operating from geostationary orbit to facilitate continuous observation of Indian sub-continent, quick monitoring of natural hazards and disaster.

GISAT carries an imaging payload consisting of of multi-spectral (visible, near infra-red and thermal), multi-resolution from 50 m to 1.5 km. It will provide pictures of the area of interest on 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.

The GISAT payload consists of:

• 700 mm Ritchey-Chretien telescope based on the Cartosat 2 design
• Array detectors in VNIR, SWIR and LWIR bands
  • High-resolution multi-spectral VNIR (HRMX - VNIR): 50 m resolution
  • High-resolution multi-spectral (HRMX - LWIR): 1.5 km resolution
  • Hyper-spectral VNIR: 320 m and 192 m resolution
  • Hyper-spectral SWIR: 320 m and 192 m resolution
• Camera electronics and data handling system
• Electronically steerable transmit antenna system
• High agility platform to enable large payload steering requirements

GISAT is built on a modified I-2K (I-2000) Bus, which is to be launched on a GSLV Mk.2A launch vehicle.

The satellite is planned to be launched in 2017 or 2018, eventually delayed to 2021. It was to operate on an orbital slot around 93.5° East, colocated with Insat 3A, Insat 4B and GSat 15. The launch in August 2021 failed.

A second satellite, GISAT 1A, is planned to be a repeat of the first satellite.