Cartosat-1 (formerly IRS-P5) is a stereoscopic

Earth observation satellite An Earth observation satellite or Earth remote sensing satellite is a satellite used or designed for Earth observation (EO) from orbit, including spy satellites and similar ones intended for non-military uses such as environmental monitoring, me ...

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 ...

, and the first one of the

Cartosat The Cartosat is a series of Indian optical earth observation satellites built and operated by the Indian Space Research Organisation (ISRO). The Cartosat series is a part of the Indian Remote Sensing Program. They are used for Earth's resourc ...

series of satellites. The eleventh satellite of ISRO in

Indian Remote Sensing Satellite 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 ...

(IRS) series. The satellite was launched 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 ...

and is operated by NTRO. Weighing around 1560 kg at launch, its applications will mainly be towards

cartography Cartography (; from grc, χάρτης , "papyrus, sheet of paper, map"; and , "write") is the study and practice of making and using maps. Combining science, aesthetics and technique, cartography builds on the premise that reality (or an im ...

in India.

Launch

It was launched by

PSLV-C6 PSLV-C6 was the sixth operational launch and overall ninth mission of the PSLV program. This launch was also the fifty-fourth launch by Indian Space Research Organisation since its first mission on 1 January 1962. The vehicle carried and injected ...

, on 5 May 2005 at 04:44:00 UTC from the newly built Second Launch Pad at Sriharikota. Images from the satellite will be available from GeoEye for worldwide distribution. The satellite covers the entire globe in 1867 orbits on a 126-day cycle. Adjacent paths are covered by a separation of eleven days.

History

Department of Space (DOS),

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, c ...

, has launched a series of satellites for Earth's resource management and monitoring. These satellites have been very successful in providing data in various scales ranging from 1:1 million to 1:12,500 scale. Each of the

Indian Remote Sensing satellite 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 ...

missions ensured data continuity while introducing improvements in the spatial, spectral and radiometric resolutions. Considering increase demand for large scale and topographic mapping data DOS launched the Cartosat-1 in 2005. Cartosat-1 is dedicated to stereo viewing for large scale mapping and terrain modelling.

Specifications

Payload

Cartosat-1 carries two state-of-the-art panchromatic (PAN) cameras that take

black and white Black-and-white (B&W or B/W) images combine black and white in a continuous spectrum, producing a range of shades of grey. Media The history of various visual media began with black and white, and as technology improved, altered to color. ...

stereoscopic pictures of 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 surfa ...

in the

visible region The visible spectrum is the portion of the electromagnetic spectrum that is visual perception, visible to the human eye. Electromagnetic radiation in this range of wavelengths is called ''visible light'' or simply light. A typical human eye wil ...

of the

electromagnetic spectrum The electromagnetic spectrum is the range of frequencies (the spectrum) of electromagnetic radiation and their respective wavelengths and photon energies. The electromagnetic spectrum covers electromagnetic waves with frequencies ranging from ...

. The swath covered by these high resolution PAN cameras is 30 km and their spatial resolution is 2.5 metres. For acquire two images simultaneously, one forward (PAN FORE) looking at +26° and one aft (PAN AFT) of the satellite at -5° for near instantaneous stereo data. The time difference between the acquisitions of the same scene by the two cameras is about 52 seconds. The spacecraft body is steerable to compensate the Earth rotation effect and to force both fore and aft cameras to look at the same ground strip when operated in stereo mode. The cameras are mounted on the satellite in such a way that near simultaneous imaging of the same area from two different angles is possible. This facilitates the generation of accurate three-dimensional maps. The cameras are steerable across the direction of the satellite's movement to facilitate the imaging of an area more frequently.

Communications

The images taken by Cartosat-1 cameras are compressed, encrypted, formatted and transmitted to the ground stations. The images are reconstructed from the data received at the ground stations. The National Remote Sensing Centre is responsible for acquisition, processing of data relayed by the Cartosat-1. A spherical Phased Array Antenna with steerable beam is used to transmit the data to the required ground station. A solid state recorder with 120 Gb capacity to store about 9 minutes of payload data is available for global operation of the payloads. The stored images can be transmitted when the satellite comes within the visibility zone of a ground station.

Optics and detectors

Each Panchromatic camera consists of three 3 mirror off-axis all reflective telescope with primary, secondary and tertiary mirrors. These mirrors are made from special zerodur glass blanks and are light weighted to about 60%. These mirrors are polished to an accuracy of l/80 and are coated with enhanced aluminium oxide (AlO₂) coating. In order to meet the high resolution and the swath requirement a 12K, 7 µm linear array

charge-coupled device A charge-coupled device (CCD) is an integrated circuit containing an array of linked, or coupled, capacitors. Under the control of an external circuit, each capacitor can transfer its electric charge to a neighboring capacitor. CCD sensors are a ...

(CCD) is used as a detector.Indian Remote Sensing Satellite Cartosat-1: Technical features and data products
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Imaging capabilities

Spatial resolution

* 2.5 m panchromatic band (0.5-0.85 µm)

Temporal resolution

The revisit rate for Cartosat-1 is five days.

Radiometric resolution

The sensor collects data with a 10-bit sensitivity.

Swath

30 km (PAN-F) and 25 km (PAN-A)

References

External links

Cartosat-1 website
{{Orbital launches in 2005 Cartosat Spacecraft launched in 2005 Spacecraft launched by PSLV rockets