Oceansat-2 is the second Indian satellite built primarily for ocean applications. It was a part of the

Indian Remote Sensing Programme India's remote sensing program was developed with the idea of applying space technologies for the benefit of humankind and the development of the country. The program involved the development of three principal capabilities. The first was to desi ...

satellite series. Oceansat-2 is an Indian satellite designed to provide service continuity for operational users of the Ocean Colour Monitor (OCM) instrument on

Oceansat-1 Oceansat-1 or IRS-P4 was the first Indian satellite built primarily for ocean applications. It was a part of the Indian Remote Sensing Programme satellite series. The satellite carried an Ocean Colour Monitor (OCM) and a Multi-frequency Scannin ...

. It will also enhance the potential of applications in other areas. The OceanSat-2 mission was approved by the

government of India The Government of India ( ISO: ; often abbreviated as GoI), known as the Union Government or Central Government but often simply as the Centre, is the national government of the Republic of India, a federal democracy located in South Asia, ...

on 16 July 2005.

Objectives

The mission objectives of Oceansat-2 are to gather systematic data for oceanographic, coastal and atmospheric applications. The main objectives of OceanSat-2 are to study surface winds and ocean surface strata, observation of

chlorophyll Chlorophyll (also chlorophyl) is any of several related green pigments found in cyanobacteria and in the chloroplasts of algae and plants. Its name is derived from the Greek words , ("pale green") and , ("leaf"). Chlorophyll allow plants to ...

concentrations, monitoring of

phytoplankton Phytoplankton () are the autotrophic (self-feeding) components of the plankton community and a key part of ocean and freshwater ecosystems. The name comes from the Greek words (), meaning 'plant', and (), meaning 'wanderer' or 'drifter'. ...

blooms, study of atmospheric

aerosol An aerosol is a suspension of fine solid particles or liquid droplets in air or another gas. Aerosols can be natural or anthropogenic. Examples of natural aerosols are fog or mist, dust, forest exudates, and geyser steam. Examples of anthropogen ...

s and suspended

sediment Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand ...

s in the water. Oceansat-2 is second satellite in the series of

Indian Remote Sensing India's remote sensing program was developed with the idea of applying space technologies for the benefit of humankind and the development of the country. The program involved the development of three principal capabilities. The first was to desi ...

satellites dedicated to ocean research, and will provide continuity to the applications of Oceansat-1 (launched in 1999). Oceansat-2 carried three instruments including an Ocean Colour Monitor (OCM-2), similar to the device carried on Oceansat-1. Data from all instruments are made available to the global scientific community after the post-launch sensor characterization, which is expected to be completed within 6 months of the launch. Oceansat-2 carry three instruments for ocean-related studies, namely, Ocean Colour Monitor-2 (OCM-2), an OceanSat Scatterometer by

Indian Space Research Organisation The Indian Space Research Organisation (ISRO; ) is the national space agency of India, headquartered in Bengaluru. It operates under the Department of Space (DOS) which is directly overseen by the Prime Minister of India, while the Chairman o ...

(ISRO), and an instrument called ROSA (Radio Occultation Sounder of the Atmosphere) developed by the

Italian Space Agency The Italian Space Agency ( it, Agenzia Spaziale Italiana; ASI) is a government agency established in 1988 to fund, regulate and coordinate space exploration activities in Italy. The agency cooperates with numerous national and international enti ...

(ASI). The major applications of data from Oceansat-2 are the identification of potential fishing zones, sea state forecasting, coastal zone studies, and inputs for

weather forecasting Weather forecasting is the application of science and technology to predict the conditions of the atmosphere for a given location and time. People have attempted to predict the weather informally for millennia and formally since the 19th cen ...

and climatic studies.

Instruments

The scientific payload contains three instruments. Two are Indian (

ISRO The Indian Space Research Organisation (ISRO; ) is the national space agency of India, headquartered in Bengaluru. It operates under the Department of Space (DOS) which is directly overseen by the Prime Minister of India, while the Chairman o ...

) and one is from the

(ASI). * Ocean Colour Monitor-2 (OCM-2) is an 8-band multi-spectral camera operating in the Visible –

Near-infrared spectroscopy Near-infrared spectroscopy (NIRS) is a spectroscopic method that uses the near-infrared region of the electromagnetic spectrum (from 780 nm to 2500 nm). Typical applications include medical and physiological diagnostics and research inc ...

spectral range. This camera provides an instantaneous geometric field of view of 360 metres and a swath of 1420 km. OCM-2 can be tilted up to +20° along track. * Radio Occultation Sounder of the Atmosphere (ROSA) is a new GPS occultation receiver provided by Italian Space Agency (ASI). 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. * OceanSat Scatterometer (OSCAT) is an active microwave device designed and developed at ISRO/SAC,

Ahmedabad Ahmedabad ( ; Gujarati: Amdavad ) is the most populous city in the Indian state of Gujarat. It is the administrative headquarters of the Ahmedabad district and the seat of the Gujarat High Court. Ahmedabad's population of 5,570,585 (per ...

. It will be used to determine ocean surface level wind vectors through estimation of radar

backscatter In physics, backscatter (or backscattering) is the reflection of waves, particles, or signals back to the direction from which they came. It is usually a diffuse reflection due to scattering, as opposed to specular reflection as from a mirror, a ...

. 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

Ku-band The Ku band () is the portion of the electromagnetic spectrum in the microwave range of frequencies from 12 to 18 gigahertz (GHz). The symbol is short for "K-under" (originally german: Kurz-unten), because it is the lower part of the ori ...

pencil beam In optics, a pencil or pencil of rays is a geometric construct used to describe a beam or portion of a beam of electromagnetic radiation or charged particles, typically in the form of a narrow beam (conical or cylindrical). Antennas which stron ...

scatterometer is an active

microwave radar Radar is a detection system that uses radio waves to determine the distance (''ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weat ...

operating at 13.515

GHz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one he ...

providing a ground resolution cell of size 50 x 50 km. It consists of a parabolic dish antenna of 1 metre diameter which is offset mounted with a cant angle of about 46° 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 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 an improved version of the one on

. 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.

Launch

Oceansat-2 was launched from

Satish Dhawan Space Centre Satish Dhawan Space Centre - SDSC (formerly Sriharikota Range - SHAR) is a rocket launch centre ( spaceport) operated by Indian Space Research Organisation (ISRO). It is located in Sriharikota, Tirupati district of Andhra Pradesh. Sriharikota ...

, First Launch Pad (FLP) on 23 September 2009, at 06:21 UTC using the

Polar Satellite Launch Vehicle The Polar Satellite Launch Vehicle (PSLV) is an expendable medium-lift launch vehicle designed and operated by the Indian Space Research Organisation (ISRO). It was developed to allow India to launch its Indian Remote Sensing (IRS) satellites ...

( PSLV-C14). India successfully launched its 16th remote-sensing satellite Oceansat-2 and six nano European satellites in 1200 seconds. The 44.4-metre tall, 230-tonne Indian launch vehicle Polar Satellite Launch Vehicle (PSLV) freed itself from the launch pad at the spaceport and lifted itself up, lugging the 970-kg Oceansat-2 and the six nano satellites all together weighing 20 kg. In copybook style, the launch vehicle first flung out Oceansat-2 at an altitude of 720 km above the

Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's sur ...

in a

Sun-synchronous orbit A Sun-synchronous orbit (SSO), also called a heliosynchronous orbit, is a nearly polar orbit around a planet, in which the satellite passes over any given point of the planet's surface at the same local mean solar time. More technically, it is ...

(SSO), followed by the four nano satellites - also called

Cubesats A CubeSat is a class of miniaturized satellite based around a form factor consisting of cubes. CubeSats have a mass of no more than per unit, and often use commercial off-the-shelf (COTS) components for their electronics and structure. CubeSat ...

, each weighing 1 kg. The remaining two, each weighing 8 kg, were attached to the fourth stage. Of the six nano satellites, four are from

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwee ...

, one is from

Switzerland ). Swiss law does not designate a ''capital'' as such, but the federal parliament and government are installed in Bern, while other federal institutions, such as the federal courts, are in other cities (Bellinzona, Lausanne, Luzern, Neuchâtel ...

and one from

Turkey Turkey ( tr, Türkiye ), officially the Republic of Türkiye ( tr, Türkiye Cumhuriyeti, links=no ), is a transcontinental country located mainly on the Anatolian Peninsula in Western Asia, with a small portion on the Balkan Peninsula ...

. The seventh is a big one, India's Oceansat-2 weighing 970 kg. Soon after the satellites were put into orbit, Indian Space Research Organisation's (ISRO) satellite tracking centres started monitoring them. This was the 16th PSLV mission.

Mission

Oceansat-2 was successfully deployed to predict the landfall and mitigate the effects of

Cyclone Phailin Extremely Severe Cyclonic Storm Phailin (; th, ไพลิน, translit=Phịlin, lit=sapphire) was the most intense tropical cyclone to make landfall in India since the 1999 Odisha cyclone until Cyclone Amphan hit West Bengal in May 2020. The s ...

, in October 2013. The OceanSat Scatterometer (OSCAT) on Oceansat-2 has been dysfunctional since February 2014.

References

{{Orbital launches in 2009 Earth observation satellites of India ISRO satellites Spacecraft launched in 2009 2009 in India Oceanographic satellites

Objectives

Instruments

Launch

Mission

See also

References