After attracting world attention last month by launching the country’s first “spy satellite,” the Indian Space Research Organization (ISRO) is already planning to launch the indigenously built Oceansat-2 satellite by July end or July.

G Madhavan Nair, Chairman, ISRO

“It will be a unique mission and the satellite would enable us to study the sea surface, wind and also track down the fishing zones,” Nair told reporters on the sidelines of a national seminar on ‘Aerospace Expanding Frontiers-Technologies and Challenges’.

“We are planning the mission by July end or early August from the launch pad in Sriharikota,” he said.

“Chandrayaan has completed its mission and it was a 100 per cent success,” Nair said when asked about the country’s first moon-mission.

“We have mapped the entire lunar surface and the data collected have been given to scientific community for analysing, results of which will be out soon,” he said.

About OceanSat-2

Oceansat-2 is an Indian satellite envisaged to provide service continuity for the operational users of OCM (Ocean Color Monitor) data as well as to enhance the application potential in other areas.

Payload

The scientific payload contains three instruments. Two are Indian and one is from the Italian Space Agency.

• Ocean Colour Monitor (OCM) – OCM is a 8-band multi-spectral camera operating in the Visible – Near IR spectral range. This camera provides an instantaneous geometric field of view of 360 meter and a swath of 1420 km. OCM can be tilted up to + 20 degree along track. The Ku-band pencil beam scatterometer is an active microwave radar operating at 13.515 GHz providing a ground resolution cell of size 50 x 50 km. It consists of a parabolic dish antenna of 1 meter diameter which is offset mounted with a cant angle of about 46 degree with respect to earth viewing axis. This antenna is continuously rotated at 20.5 rpm using a scan mechanism with the scan axis along the +ve Yaw axis. By using two offset feeds at the focal plane of the antenna, two beams are generated which will conically scan the ground surface. The back scattered power in each beam from the ocean surface is measured to derive wind vector. It is a improved version of the one on Oceansat-1.

• Scanning Scatterometer (SCAT) – SCAT is an active microwave device designed and developed at ISRO/SAC, Ahmedabad. It will be used to determine ocean surface level wind vectors through estimation of radar backscatter. The scatterometer system has a 1-m parabolic dish antenna and a dual feed assembly to generate two pencil beams and is scanned at a rate of 20.5 rpm to cover the entire swath. The inner beam makes an incidence angle of 48.90° and the outer beam makes an incidence angle of 57.60° on the ground. It covers a continuous swath of 1400 km for inner beam and 1840 km for outer beam respectively. The inner and outer beams are configured in horizontal and vertical polarization respectively for both transmit and receive modes. The aim is to provide global ocean coverage and wind vector retrieval with a revisit time of 2 days.

• Radio Occultation Sounder for Atmospheric Studies (ROSA) – ROSA is a new GPS occultation receiver provided by ASI (Italian Space Agency). The objective is to characterize the lower atmosphere and the ionosphere, opening the possibilities for the development of several scientific activities exploiting these new radio occultation data sets.

The satellite will be launched by India’s tried and tested space launch vehicle, the Polar Satellite Launch Vehicle (PSLV) and will lift off from Sriharikotta.

Data from all instruments will be made available to the global scientific community after the post-launch sensor characterization, which is expected to be completed within 6 months from the launch.

GSAT-4

ISRO is also planned to launch the expiremental communications satellite GSAT-4 also designated as HealthSat in August. The satellite will also be accompanied by the Israeli astronomy satellite Tuavex-2. This will be launched using the Geosynchronous Satellite Launch Vehicle (GSLV) from Sriharikotta.

“GSAT-4 is getting ready and everything has been set to launch it into space in August,” said M Krishnaswamy, Programme Director, ISAC, ISRO. When launched, the satellite should be able to provide better internet connectivity in remote areas of the country, he said.

Giving details of the satellite, Krishnaswamy said it was primarily constructed as a technology demonstrator.

“We had been using KU-band technology for our satellites before. With this KA-Band technology, we would be able to upgrade our band communication and navigation payload,” he informed.

“It is a very futuristic satellite and will be at par with all the existing communication satellites. It will have a GPS receiver and digital connectivity on board, so that it can help in connecting the remote villages through internet,” he said.