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. 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 15919, ISO: Bhārata Sarakāra, legally the Union Government or Union of India or the Central Government) is the national authority of the Republic of India, located in South Asia, consisting of States and union t ...

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 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 allows plants to absorb energy ...

concentrations, monitoring of

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

blooms, study of atmospheric

aerosol An aerosol is a suspension (chemistry), suspension of fine solid particles or liquid Drop (liquid), droplets in air or another gas. Aerosols can be generated from natural or Human impact on the environment, human causes. The term ''aerosol'' co ...

s and suspended

sediment Sediment is a solid material that is transported to a new location where it is deposited. It occurs naturally and, through the processes of weathering and erosion, is broken down and subsequently sediment transport, transported by the action of ...

s in the water. Oceansat-2 is second satellite in the series of Indian Remote Sensing 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 India's national List of government space agencies, space agency, headquartered in Bengaluru, Karnataka. It serves as the principal research and development arm of the Department of Space (DoS), ...

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

Italian Space Agency The Italian Space Agency (; 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 entities who are active in aerospac ...

(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 or weather prediction is the application of science and technology forecasting, to predict the conditions of the Earth's atmosphere, atmosphere for a given location and time. People have attempted to predict the weather info ...

and climatic studies.

Instruments

The scientific payload contains three instruments. Two are Indian (

ISRO The Indian Space Research Organisation (ISRO ) is India's national space agency, headquartered in Bengaluru, Karnataka. It serves as the principal research and development arm of the Department of Space (DoS), overseen by the Prime Minister 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 The Global Positioning System (GPS) is a satellite-based hyperbolic navigation system owned by the United States Space Force and operated by Mission Delta 31. It is one of the global navigation satellite systems (GNSS) that provide geol ...

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 ( ), also spelled 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 ...

. 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, ...

. The

scatterometer A scatterometer or diffusionmeter is a scientific instrument to measure the return of a beam of light or radar waves scattered by diffusion in a medium such as air. Diffusionmeters using visible light are found in airports or along roads to measur ...

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 Revolutions per minute (abbreviated rpm, RPM, rev/min, r/min, or r⋅min−1) is a unit of rotational speed (or rotational frequency) for rotating machines. One revolution per minute is equivalent to hertz. Standards ISO 80000-3:2019 def ...

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 ), because it is the lower part of the original NATO K band ...

pencil beam In optics, a pencil or pencil of rays, also known as a pencil beam or narrow beam, is a geometric construct (pencil of half-lines) used to describe a Light beam, beam or portion of a beam of electromagnetic radiation or charged subatomic particl ...

is an active microwave radar operating at 13.515

GHz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), often described as being equivalent to one event (or Cycle per second, cycle) per second. The hertz is an SI derived unit whose formal expression in ter ...

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 Oceansat-1. 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 the primary spaceport of the Indian Space Research Organisation (ISRO), located in Sriharikota, Tirupati district, Andhra Pradesh. The spaceport is located on an isl ...

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

UTC Coordinated Universal Time (UTC) is the primary time standard globally used to regulate clocks and time. It establishes a reference for the current time, forming the basis for civil time and time zones. UTC facilitates international communica ...

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) satellite ...

( 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 Planetary habitability, harbor life. This is enabled by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all ...

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 small satellite with a form factor of cubes. CubeSats have a mass of no more than per unit,, url=https://static1.squarespace.com/static/5418c831e4b0fa4ecac1bacd/t/5f24997b6deea10cc52bb016/1596234122437/CDS+REV14+2020-07-3 ...

– 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 lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...

, one is from

Switzerland Switzerland, officially the Swiss Confederation, is a landlocked country located in west-central Europe. It is bordered by Italy to the south, France to the west, Germany to the north, and Austria and Liechtenstein to the east. Switzerland ...

and one from

Turkey Turkey, officially the Republic of Türkiye, is a country mainly located in Anatolia in West Asia, with a relatively small part called East Thrace in Southeast Europe. It borders the Black Sea to the north; Georgia (country), Georgia, Armen ...

. 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 (; ) was one of the most intense tropical cyclones to make landfall in India since the 1999 Odisha cyclone. The system was first noted as a tropical depression on October 4, 2013, within the Gulf of Thailand ...

, 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