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0.1. Introduction

Several nations operate or plan to operate satellite remote sensing systems specifically designed for observation of earth resources, including crops, forests, water bodies, land use, and minerals. Satellite sensors offer several advantages over aerial photography; they provide a synoptic view (observation of large areas in a single image), as well as fine detail and systematic, repetitive coverage.

0.2. Remote SensingRemote sensing is the science of acquiring information about the Earth's surface without actually being in contact with it. It is the observation and measurement of objects from a distance, i.e. instruments or recorders are not in direct contact with objects under investigation. Figure: How Remote Sensing works 0.3. Early History of Space imaging Remote sensing from space received its first impetus through remote sensing from rockets. As early as 1891, a patent was granted to Ludwig Rahrmann of Germany for a “New or Improved Apparatus for Obtaining Bird’s Eye Photographic Views”

Space Remote Sensing began in earnest during the period 1946 to 1950 when small cameras were carried aboard captured V-2 rockets. Also beginning in 1960 was an early U.S. military space imaging reconnaissance program, called Corona. Consequently, the exciting future for remote sensing from space only become apparent to the civilian community as part of the manned space programs of the 1960’s: Mercury, Gmini, and Apollo.

In 1973, Skylab, the first American space workshop, was launched and its astronauts took over 35,000 images of the earth with the Earth Resources Experiment Package (EREP). Another early (1975) space station experiment having a remote sensing component was the joint U.S.-USSR Apollo-Soyuz Test Project (ASTP).

0.4. Brief History of satellite Remote Sensing Program

The story begins in 1952, when the International Council of Scientific Unions decided to establish July 1, 1957, to December 31, 1958, as the International Geophysical Year (IGY) because the scientists knew that the cycles of solar activity would be at a high point then. In October 1954, the council adopted a resolution calling for artificial satellites to be launched during the IGY to map the Earth's surface.

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History changed on October 4, 1957, when the Soviet Union successfully launched Sputnik I. The world's first artificial satellite was about the size of a basketball, weighed only 183 pounds, and took about 98 minutes to orbit the Earth on its elliptical path.

In July 1955, the White House announced plans to launch an Earth-orbiting satellite for the IGY and solicited proposals from various Government research agencies to undertake development. In September 1955, the Naval Research Laboratory's Vanguard proposal was chosen to represent the U.S. during the IGY.

The Sputnik launch also led directly to the creation of National Aeronautics and Space Administration (NASA). In July 1958, Congress passed the National Aeronautics and Space Act (commonly called the "Space Act"), which created NASA as of October 1, 1958 from the National Advisory Committee for Aeronautics (NACA) and other government agencies.

On January 31, 1958, the tide changed, when the United States successfully launched Explorer-I. This satellite carried a small scientific payload that eventually discovered the magnetic radiation belts around the Earth, named after principal investigator James Van Allen.

0.4.1. Explorer-1 and Jupiter-C Explorer-I, officially known as Satellite 1958 Alpha, was the first United States earth satellite and was sent aloft as part of the United States program for the International Geophysical Year 1957-1958.

0.4.2. Applications Satellites NASA did pioneering work in space applications such as communications satellites in the 1960s. The Echo, Telstar, Relay, and Syncom satellites were built by NASA or by the private sector based on significant NASA advances.

0.4.3. Communications Satellites Starts with a useful overview of the early history of satellite communications and includes information on NASA's current Advanced Communications Technology Satellite.

0.4.4. Weather Satellites Check out information on programs such as Tiros and Nimbus.

0.4.5. Earth Science Satellites NASA has been involved with projects ranging from Landsat to TOPEX/POSEIDON and the Earth Observing System (EOS).

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0.5. Timeline of spaceflight

This is a timeline of known spaceflights, both manned and unmanned, sorted chronologically by launch date. Owing to its large size, the timeline is split into smaller articles, one for each year since 1951. There is a separate list for all flights that occurred before 1951.

For the purpose of this article, a "spaceflight" is defined as any flight that crosses the Karman line, the officially recognised "edge of space", which is 100 kilometres (62.14 miles) AMSL. The timeline contains all flights which have done so, were intended to do so, but failed, or are planned to do so in the not-too-distant future.

Orbital launch rates

1.0. CORONA Corona is the project designation for the satellite reconnaissance system operated by the United Sates during the interval 1960-1972. Corona provided photographic imagery that was interpreted to provide strategic intelligence on the activities of Soviet industry and strategic forces. Details of the system, the schedule, nature of the imagery, and the ability to interpreters to derive information from the imagery were closely guarded secrets.

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Figure: The absolute orientation of the CORONA images using surficial fiducial marks.

1.1. Satellite and OrbitThe reconnaissance satellites were placed into near-polar orbits, with, for example, an inclination of 77 degree, apogee of 502 miles, perigee of 116 miles. Initially mission would last only 1 day; by the end of the program, mission extended for 16 days. The recovery vehicle was designed to withstand the heat of reentry into the earth’s atmosphere and to deploy parachute at an altitude of about 60,000 ft. The capsule was then recovered in the air by specially designed aircraft. Recoveries were planned for the Pacific ocean near Hawwaii.

1.2. ApplicationCorona provided the first satellite imagery of the earth’s surface, and thus extended the historical record of the satellite imagery into the late 1995s, about 10years before Landsat. Therefore, it may be able to assist in assessment of Environmental change, trends in human use of the landscape, and similar phenomena.

Ruffner (1995) provides examples that show archaeological and geologic applications of Corona imagery, and other application may not yet be identified.

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Application of Corona Satellite Photograph in Engineering and ScienceDue to higher spatial resolution, synoptic view,wide area coverage and stereoscopic capabilitiy, these photographs resulted in an extraordinary range of applications.These includes:

(a) Change detection studies: CORONA photographs are useful for studing changes in urban area, transportation network, forest density and extent, surface geomorphology (river course shifting, landslide etc.).

(b) Mapping Studies:To generate DEMs and thematic maps for inaccessible areas

where data ffrom other sources (like survey of India maps) are not available.

(c) Archaeological Studies: The high resolution information from CORONA photographs can be employed for detecting archaeological sites.

(d) Tectonic Studies: 3d stereo views can help in the interpretation of tectonic signatures (lanform). CORONA photographs with higher resolution, extensive coverage, low cost and stereo ability can prove useful for this purpose.

(e) Military Application: CORONA photographs also serve as a rich resource for military to map their own and inaccessible enemy territory.

2.0. LandsatLandsat (land satellite)was design in the 1960s and launched in 1972as the first satellite tailored specifically for broad scale observation of the Earth’s land areas to accomplish for land resource studies. It was proposed by the sciencetist and administrators in the U.S. government who envisioned application of the principles of remote sensing to broad-scale, repetitive survey of the earth’s land arreas.

The U.S. Landsat Mission has collected remotely sensed imagery of the Earth’s surface for more than 35 years. The National Aeronautics and Space Administration(NASA) and U.S. Geological Survey(USGS) jointly operate Landsat. The two agencies are developing a follow-on initiative known as the Landsat Data Continuity Mission(LDCM).

2.1. Characteristics of Landsat satelliteLandsat sensor record reflected and emitted energy from Earth’s in various wavelengths of the electromagnetic spectrum. The electromagnetic spectrum includes all forms of radiated energy from tiny gamma rays x-rays all the way to huge radio waves.

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2.2. Different Landsat MissionThe Landsat system consist of spacecraft-borne sensors that observe the earth and transmit information by microwave signals to gr4ound stations that receive, and then process, data for dissemination to a community of data users. Early landsat vehicles carries two sensor systems; the return beam vidicon (RBV) and the multispectral scanner subsystem (MSS).The second generation of landsat vehicales (landsats 4 and 5) carried the MSS, as well as the thematic mapper-a more sophisticated version of the MSS.

2.3. Application Landsat has been used in a wide variety of applications, Climate research, natural

resource management, commercial and municipal land development, public safety, homeland security and natura disaster management.

Landsat data have been used to monitor water quality, glacier recession, sea ice movement, invasive species encroachment, coral reef health, land use change, deforestation rates and population growth.

Landsat has also helped to assess demage from natural disasters such as fires, floods and tsunamis, and subsequently, plan disaster relief and flood control programs.

The long term continuity of landsat allows users to go back in time to monitor changes in the Earth’s surface.

2.4. The future of Landsat

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The lack of a permanent agency home for landsat was a major factor in the impending data gap in the landsat series and planning for a follow-on instrument after the five year life of LDCM-1 is still in limbo. The FLI-IWG report recommended that long-term responsibilities for land imaging including Landsat planning and operations, be permanently placed under a National Land Imaging Program at the Department of the Interior. Implementation and funding for that program continue to be discussed, but the FY2010 USGS budget document does not include any substantive reference to NLIP.

3.0. SPOTSpot (Satellite Pour l'Observation de la Terre) is a high-resolution, optical imaging Earth observation satellite system operating from space. It is run by Spot Image based in Toulouse, France. It was initiated by the CNES (Centre national d'études spatiales — the French space agency) in the 1970s and was developed in association with the SSTC (Belgian scientific, technical and cultural services) and the Swedish National Space Board (SNSB).

The SPOT system includes a series of satellites and ground control resources for satellite control and programming, image production, and distribution. The satellites were launched with the ESA rocket launcher Ariane 2, 3, and 4.

SPOT 1 launched February 22, 1986 with 10 panchromatic and 20 metre multispectral picture resolution capability. Withdrawn December 31, 1990.

SPOT 2 launched January 22, 1990 and is still operational. SPOT 3 launched September 26, 1993. Stopped functioning November 14, 1997 SPOT 4 launched March 24, 1998 SPOT 5 launched May 4, 2002 with 2.5 m, 5 m and 10 m capability

3.1. The SPOT orbit

The SPOT orbit is polar, circular, sun-synchronous, and phased. The inclination of the orbital plane combined with the rotation of the Earth around the polar axis allows the satellite to fly over any point on Earth within 26 days. The orbit has an altitude of 832 kilometers, an inclination of 98.7°, and completing 14 + 5/26 revolutions per day.

3.2. SPOT 1, 2, and 3

Since 1986 the SPOT family of satellites has been orbiting the Earth and has already taken more than 10 million high quality images. SPOT 1 was launched with Ariane 2 on February 22, 1986. Two days later, the 1800 kg SPOT 1 transmitted its first image with a spatial resolution of 10 or 20 meters. SPOT 2 joined SPOT 1 in orbit on January 22, 1990 and SPOT 3 followed on September 26, 1993.

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The satellite loads were identical, each including two identical HRV (High Resolution Visible) imaging instruments that were able to operate in two modes, either simultaneously or individually. The two spectral modes are panchromatic and multispectral. They have a scene size of 3600km2 and a revisit interval of one to four days, depending on the latitude.

3.4. SPOT 4

SPOT 4 was launched on March 24, 1998 and features major improvements over SPOT 1, 2, and 3. The principal feature was the modification of the HRV, becoming a high-resolution visible and infrared (HRVIR) instrument. It has an additional band at mid-infrared wavelengths (1.58-1.75 micrometre), intended to provide capabilities for geological reconnaissance, vegetation surveys, and survey of snow cover, with a resolution of 20 meters. Its lifetime was increased from three to five years, and its telescopes and recording capacities were improved.

3.5. SPOT 5

SPOT 5 was launched on May 4, 2002 and has the goal to ensure continuity of services for customers and to improve the quality of data and images by anticipating changes in market requirements. SPOT 5 has two high resolution geometrical (HRG) instruments that were deduced from the HRVIR of SPOT 4. They offer a higher resolution of 2.5 to 5 meters in panchromatic mode and 10 meters in multispectral mode.

3.6. Future

The Pleiades satellites program is intended to complement the SPOT satellites. It will use a constellation of smaller, more agile satellites offering an improved spatial resolution of up to 0.7 metres. Launch of the first satellite, PLEIADES-HR 1, is scheduled for the beginning of 2010.

3.6. Application of Spot Program

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4.0. Indian remote sensing satellite

During the 1970’s and 80’s, India’s remote sensing data needs were being addressed by foreign satellites like LANDSAT, NOAA, SPOT etc., where NRSA just procured the satellite data products from foreign agencies and supplied it to the users.. With the setting up of an Earth Station at Hyderabad in 1979, satellite data reception started, first from USA’s LANDSAT satellite.

4.1. History of IRS

The launch of India’s first civilian remote sensing satellite IRS-1A in March 1988, marked the beginning of a successful journey in the course of the Indian Space Programme. The two LISS sensors aboard IRS-1A beamed down valuable data that aided in large scale mapping applications.

Subsequently, IRS-1B, having similar sensors, was launched in August 1991, and together, they provided better repetivity. The LISS-III, PAN and WiFS sensors on IRS-

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MARITIME APPLICATIONS : Locating and tracking ships at sea

HAZARD MANAGEMENT : Greek Fires: SPOT 5 shows the houses burned

MARITIME APPLICATIONS : Integrating satellite imagery in an operational maritime surveillance system

FORESTRY :Combating deforestation in the Amazon: monitoring and enforcement

Cartography, cadastral mapping Defence, Intelligence, Security Agriculture Land planning and management Telecoms Energy, mines .

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1C (December 1995) and IRS-1D (September 1997) further strengthened the scope of remote sensing.

To test the launch vehicle programme, IRS-P3 and IRS-P4 satellites were launched. IRS-P3 carried an X-ray astronomy payload for space science studies, besides a WiFS and MOS sensors.

The launch of IRS-P6 (Resourcesat-1) in October 2003, provided an excellent opportunity to obtain high resolution multi-spectral data and moderate resolution data in 10-bi, while providing continuity of data.

IRS-P5 (Cartosat-1), launched on May 5, 2005, catapulted the Indian Remote Sensing program into the world of large scale mapping and terrain modeling applications.

Resolution (m) Sensor Satellite

360 OCM IRS-P4

180 WIFS IRS 1C, IRS 1D,IRS P3

72.5 LISS – I IRS 1A, IRS 1B

56 AWIFS IRS P6

36.25 LISS_II IRS 1A, IRS 1B

24 LISS-III IRS 1C, IRS 1D

5 PAN,LISS-IV IRS 1C, IRS 1D, IRS P6

2.5 PAN IRS P5

0.8 PAN CARTOSAT-2

4.1. IRS-1A

IRS-1A is the first satellite in the IRS constellation. It was launched from Baikonur cosmodrome, Khazakhstan. It operated in sun-synchronous near polar orbit at an inclination of 99 degrees at an altitude of 904 km. One orbit around the earth took about 103 minutes and the satellite made 14 orbits per day.

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Orbit Polar Sun synchronous

Altitude 904 Km

Inclination 99 degrees

Local Time 9:40 A.M

Repetivity 22 Days

Orbits/day 14

Period 103 minutes

Sensors LISS-I, LISS-II

It had two types of cameras known as Linear Self Scanning Sensors (LISS-I and LISS-II). LISS-I had a spatial resolution of 72.5m with a swath of 148 km on ground. LISS-II had two separate imaging sensors LISS-IIA and LISS-IIB with spatial resolution of 36.25m each. Both LISS-I and LISS-II operated in four spectral bands covering visible and near infrared region. It had following payload and orbital parameters.

4.1.1. LISS-1, LISS - II sensor characteristics

4.2. IRS-1B

IRS-1B is the second satellite in the Indian remote sensing series. It was launched from Baikanur cosmodrome, Kazakhstan. IRS-1B is identical to IRS-1A in all respects. The

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payload and orbital parameters of IRS-1B are the same as that of IRS-1A. The satellite provided excellent data during the period 1991-2001, outliving its designed life. Many nation level mapping projects were carried out using the data.

It had following payload and orbital parameters

Orbit Polar Sun synchronous

Altitude 904 Km

Inclination 99 degrees

Local Time 9:40 A.M

Repetivity 22 Days

Orbits/day 14

Period 103 minutes

Sensors LISS-I, LISS-II

4.2.1. LISS-1, LISS - II sensor characteristics

4.3. IRS-1C

The fourth in the IRS series, IRS - 1C was launched from Baikanur cosmodrome, Kazakhstan on May 19, 1995. It operates in a near polar, sun- synchronous orbit at an altitude of 817km. Its local equatorial crossing time is 10:30 A.M in the descending node. The satellite payload consists of three sensors, namely Panchromatic camera (PAN), Linear Imaging and Self-Scanning Sensor (LISS - III) and Wide Field Sensor (WiFS).

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Orbit Polar, Sun synchronous

Altitude 817 Km

Inclination 98.69 deg

Local Time 10:30 A.M

Repetivity 24 Days

Orbits/cycle 341

Period 101.35 min

Sensors PAN, LISS-III, WiFS

The PAN camera provides data with a spatial resolution of 5.8m and a ground swath of 70 km at nadir view. This camera can be steered up to + 26 degrees, which can be used to acquire stereo pairs and this also improves the revisit capability to 5 days.

LISS - III camera provides multi-spectral data in 4 bands. The spatial resolution for visible (two bands) and near infrared (one band) is 23.5m with a ground swath of 141 km. The fourth band (short wave infrared band) has a spatial resolution of 70.5m with a ground swath of 148 km. The repetivity of LISS - III is 24 days.

WiFS camera collects data in two spectral bands with a spatial resolution of 188m and a ground swath of 810 km. By virtue of its wide swath there is huge side lap between adjacent paths. A repetivity of 3 days can be achieved by suitably combining paths.

The satellite is equipped with an On Board Tape Recorder (OBTR) with a capacity of 62 Gb, for collecting data outside the visibility region of any ground station. The OBTR was capable of storing data collected for 24 minutes. The OBTR was functional during 1995-1998.

4.3.1. PANCHROMATIC, LISS-III, WiFS Sensor Characteristics

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4.4. IRS-1DOn 29th September, 1996, Indian Space Research Organization (ISRO) proved its launch vehicle capability by launching the Indian Remote Sensing Satellite, IRS-1D, using Polar Satellite Launch Vehicle, PSLV-C1, from Sriharikota. This added one more member to the existing IRS constellation. It carries payloads similar to its predecessor, IRS-1C. Like IRS-1C, IRS-1D has LISS III, PAN, WiFS sensors onboard.

Orbit Near Polar, Sun synchronous

Altitude 737 km (perigee)821 km (apogee)

Inclination 98.53 deg

Local Time 10.30 A.M to 10.47 A.M

Repetivity 25 days

Orbits/cycle 358

Period 100.56 minutes

Sensors PAN, LISS-III, WIFS

4.3.1. PANCHROMATIC, LISS-III, WiFS Sensor Characteristics

4.5. IRS-P3

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The IRS-P3 satellite was launched from Sriharikota, India, using Polar Satellite Launch Vehicle – PLSV-D3. IRS-P3 was put in a polar, sun-synchronous orbit at an altitude of 817km with equatorial crossing time of 10:30 A.M in the descending node.

Orbit Near Polar, Sun synchronous

Altitude 817km

Inclination 98.69 deg

Local Time 10.30 A.M

Repetivity 24 days

Orbits/cycle 341

Period 101.35 min

Sensors WiFS, MOS-A, MOS-B,MOS-C

IRS - P3 has an X-ray astronomy and two remote sensing payloads, namely Wide Field Sensor (WiFS) and Modular Optoelectronics Scanner (MOS). The mission caters to oceanography applications.

IRS - P3 WiFS is similar to IRS - 1C WiFS but for the inclusion of an additional band in the Middle Infra-red (MIR) region. This sensor is primarily meant for vegetation dynamic studies while MOS is meant for ocean related studies. MOS has helped the ocean application scientists in developing necessary algorithms for extracting ocean parameters such as phytoplankton, yellow substance and suspended sediments in ocean waters.

4.5.1. WiFS, MOS Sensor Characteristics

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4.6. IRS-P4The IRS-P4 (Oceansat-1), the eighth satellite built in India under the indigenous Indian Remote Sensing Satellite programme was successfully launched on May,26,1999 at 11.52 A.M from Sriharikota, India using the indigenously developed Polar Satellite Launch Vehicle (PSLV).

Orbit Polar, Sun synchronous

Altitude 720 km

Inclination 98.38 deg

Local Time Noon +/- 20 minutes in descending node

Repetivity 2

Orbits/cycle 29

Period 98 minutes

Sensors OCM , MSMR

IRS-P4 carries two sensors onboard, Ocean Color Monitor (OCM) and Multi-frequency Scanning Microwave Radiometer (MSMR). Several new technologies like Dual Cone Earth Sensor, improved Digital Sun Sensor and Satellite Positioning System (SPS) were introduced in the satellite. OCM data products are available to the User community acquired from July,01,1999 onwards.

4.6.1. Ocean Color Monitor (OCM)

OCM is a eight channel sensor, operating in the visible and NIR regions of the electromagnetic spectrum.

The OCM camera can be tilted by +/- 20 degrees in the along track direction, to avoid the sun glint. As the OCM has narrow bands and the total upwelling radiation from ocean surface is weak, the sensor is so designed to give a high radiometric performance, spanning the entire dynamic range. Also, the field of view of the optics is + 43degrees,

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providing a swath of 1420km, from 720km altitude. This requires a complex lens design known as Telecentric.

4.6.1. Applications of OCM

Development of algorithms for retrieval of ocean and atmospheric parameters.

(a) Ocean color applications

identification of potential fishing zones in coastal waters. exploration of deep sea fishery resources . primary production model and fish stock assessment. selection and monitoring of algal blooms.

(b) Coastal processes

sediment dynamics dynamics of estuarine/tidal inlets. circulation and dispersal pattern. Upwelling; coastal/oceanic fronts and surface currents. marine pollution and oil slicks. coral reef studies.

4.6.2. MSMR

MSMR works on the principle of collecting radiation from earth in the microwave region, which gives the brightness temperature of the surface. Physical temperature when multiplied with the emissivity of the object (here ocean water), gives the brightness temperature of the object. The radiation emitted by the ocean surface passes through earth atmosphere, gets modified and sensed by MSMR.

4.7. IRS-P5

The CARTOSAT-1 (IRS-P5) is envisaged as a mission to meet the stereo data requirements of the user community. The objectives of the mission are :

* To design, develop, launch and operate an advanced space based mission with enhanced spatial resolution (2.5m) with along track stereo viewing capability for large scale mapping applications (up to 1:5000 scale)

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* To further stimulate newer areas of cartographic applications, urban management, disaster assessment, relief planning and management, environmental impact assessment and GIS application.

CARTOSAT-1 is a global mission. The nominal life of the mission is planned to be five years. The satellite was launched by the indigenously built Polar Satellite Launch Vehicle on May 05, 2005.

The payload system of IRS-P5 consists of two Panchromatic solid state cameras - Fore and Aft, mounted at +26 degrees and -5 degrees with respect to nadir to generate stereoscopic image of the area along the track.

Major specifications of the sensors

 Parameter Specification

 Swath Fore Aft 29.42 km 26.24 km

 IGFOV Fore Aft 2.452 m (Across track) 2.187 m (Across track)

 Ground sample distance 2.54 m (Along Track)

 Spectral band 0.5 – 0.85 microns

 Quantization 10 bits (1024)

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Orbit Polar, sun-synchronous

Orbital Altitude 618 km

Semi Major Axis 6996.14 km

Eccentricity 0.001

Inclination 97.87 degrees

Local time 10:30 A.M

Revisit 5 days

Repetivity 126 days

Orbits/day 14

Period 97 minutes

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 Number of detectors 12 K

 Pixel size 7 x 7 micron

 Integration time 0.336 ms

 Focal length 1945 mm

 Data rate per Camera 336 Mbps

 Data compression Ratio 3.2:1

 Type of compression JPEG like

 Data rate transmitted to ground 105 Mbps

4.8. IRS-P6

The RESOURCESAT-1 (IRS-P6) is envisaged as the continuity mission to IRS-1C/1D, with enhanced capabilities both in the payload and the platform, to meet the increasing demands of the user community. The objectives of the mission are :

* To provide continued remote sensing data services.

* To further carry out studies in advanced areas of user applications.

The life of the mission is planned to be five years. The satellite was launched by the indigenously built Polar Satellite Launch Vehicle on October 17, 2003. The orbit parameters of IRS-P6 are same as IRS-1C.

Orbits/cycle 341

Semi major axis 7195.11 km

Altitude 817 km

Inclination 98.69 deg

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Eccentricity 0.001

Number of orbits/day 14

Orbital period 101.35 minutes

Repetivity 24 days

Distance between adjacent paths 117.5 km

Distance between successive ground tracks

2820 km

Ground trace velocity 6.65 km/sec

Equatorial crossing time 10.30 A.M (at descending node)

The payload system of IRS-P6 consists of three solid state cameras :

1. A high resolution multispectral sensor - LISS-IV

2. A medium resolution multispectral sensor - LISS-III

3. An Advanced Wide Field Sensor – AWiFS

4.8.1. LISS-IV Camera

This camera can be operated in two modes: Mono and Multi-spectral. In the Multi-spectral mode, data are collected in three spectral bands -

0.52 to 0.59 microns (Green (Band 2))

0.62 to 0.68 microns (Red (Band 3))

0.76 to 0.86 microns (NIR (Band 4))

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Major specifications of LISS-IV camera

IGFOV (Across track) 5.8 m

Ground sampling distance 5.8 m

Spectral Bands B2, B3, B4

Swath 23.9 km (multispectral mode)70 km (Mono mode)

Saturation radiance (mw/cm 2 /sr/micron)

B2 - 55 B3 - 47 B4 - 31.5

Integration time 0.877714 msec

Quantization 10 bits Selected 7 bits will be transmitted by the data handling system

No. of gains Single gain (Dynamic range obtained by sliding 7 bits out of 10 bits)

4.8.2. LISS-III camera

The LISS-III is a multi-spectral camera operating in four spectral bands, three in the visible and near infra-red and one in SWIR region, as in the case of IRS-1C/1D. The new feature in LISS-III camera is the SWIR band (1.55 to 1.7 microns), which provides data with a spatial resolution of 23.5m unlike IRS-1C/1D (the spatial resolution is 70m).

4.8.3. AWiFS Sensor

The AWiFS camera provides enhanced capabilities compared to the WiFS camera on-board IRS-1C/1D, in terms of spatial resolution (56 m Vs 188m), radiometric resolution (10 bits Vs 7 bits) and Spectral bands (4 Vs 2) with the additional feature of on-board detector calibration using LEDs. The spectral bands of AWiFS are same as LISS-III.

Major specifications of AWiFS sensor .

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IGFOV 56 m (nadir) 70 m (at field edge)

Spectral Bands B2, B3, B4 and B5

Swath 740 km (combined)370 km each head

Integration time 9.96 msec

Quantization 10 bits

No. of gains 16

4.9. Indian Mini Satellite-1

ISRO has established a space-based system to reap the benefits of remote sensing technology to the society by launching a series of IRS satellites under the Indian Remote Sensing (IRS) Programme. Keeping this in view, ISRO has launched the Indian Mini Satellite – 1 (IMS-1) on April 28, 2008 as an auxiliary satellite on PSLV-C11. The satellite carries two payloads namely, Multi-spectral camera (Mx) and Hyper-Spectral Imager (HySI). IMS-1 is a mini satellite weighing 83 kg and has a mission life of two years.

Orbit Specifications of IMS-1

  Orbit   Polar sun-synchronous

  Orbital Altitude   626 km

  Semi major Axis   7004.281 km

  Eccentricity   0.001 degrees

  Inclination   97.999 degrees

  Local time   9.30 AM (descending node)

  Orbits/day   14.79

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  Repetivity   355 orbits in 24 days

  Period   97.36 minuites

4.10. Application

The remote sensing data from this micro satellite is planned to be used for Natural resources monitoring / management like agriculture (crop condition assessment and crop acreage yield estimation), forest coverage and deforestation, urban infrastructure development, land use and waste land mapping, coastal features mapping, coral reef mapping and land slide studies.

1.0. New Generation Satellite

New generation Satellites provides high resolution satellite image that helps to discovered and discerned earth features quickly and integrated into action for all types of government agencies: defense and intelligence, state, local and civil government, as well as humanitarian relief organizations. Here the following Satellite programs are mentioned:

1. Ikonos2. DigitalGlobe

a) QuickBird

b) WorldView-1

c) WorldView-2

3. GeoEye

1.1. IkonosIkonos is a commercial earth observation satellite, and was the first to collect publicly available high-resolution imagery at 1- and 4-meter resolution. It offers multispectral (MS) and panchromatic (PAN) imagery. IKONOS imagery began being sold on January 1, 2000.Its name from the Greek term eikōn for image.

Launched on September 24, 1999, It was able to collect sub-meter imagery with 0.80-meter panchromatic and 3.2-meter multispectral resolution. IKONOS was also the most agile satellite in the industry surpassed only recently by GeoEye-1. The agility of IKONOS combined with its longevity translates into one of the most robust high resolution satellite imagery archives available.

Spatial resolution 0.8 m panchromatic (1-m PAN) 4-meter multispectral (4-m MS)

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1-meter pan-sharpened (1-m PS)

Spectral Resolution Band 1-m PAN 4-m MS & 1-m PS1 (Blue) 0.45-0.90 µm 0.445-0.516 µm2 (Green) * 0.506-0.595 µm3 (Red) * 0.632-0.698 µm4 (Near IR) * 0.757-0.853 µm

Temporal resolution The revisit rate for IKONOS is 3 to 5 days off-nadir and 144 days for true-nadir.

Radiometric resolution The sensor collects data with a 11-bit (0-2047) sensitivity and are delivered in an unsigned 16-bit (0-65535) data format.

1.1.1. Key IKONOS Specifications

Spectral Bands:Panchromatic (Black and White) & Multispectral (Red, Green, Blue and NIR)

Resolution: 0.80-m Panchromatic & 3.2-m Multispectral

Revisit Time: ~ 3 days (depends on latitude)

Positional Accuracy:15-m CE90% (does not account for topographic distortions)

Swath Width: 11.3-km at nadir

Archive Dates: September 1999 to Present

Stereo Availability: Archive (as available) and as new collections

Orbital Altitude: 681-km

Swath: 11 km x 11 km (Single Scene)

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1.2. Digital Globe

DigitalGlobe, of Longmont, Colorado, USA, is a commercial vendor of space imagery and geospatial content, and operator of civilian remote sensing spacecraft. In 1995, the company became EarthWatch Incorporated, merging WorldView with Ball Aerospace & Technologies Corp.'s commercial remote sensing operations. In September 2001, EarthWatch became Digital Globe.DigitalGlobe developing Quickbird, is the first in a constellation of spacecraft, that offers highly accurate, commercial high resolution imagery of Earth.

5.2.1.(a) QuickBird

QuickBird is a high-resolution commercial earth observation satellite, owned by DigitalGlobe and launched in october18, 2001[2]

as the first satellite in a constellation of three scheduled to be in orbit by 2008.The satellite collects panchromatic (black & white) imagery at 60-70 centimeter resolution and multispectral imagery at 2.4-2.8 m (7 ft 10 in) resolutions.

DigitalGlobe built in partnership with Ball Aerospace and Orbital Sciences, and launched by a Boeing Delta II. It is in a 450 km altitude, –98 degree inclination sun-synchronous orbit. An earlier launch attempt resulted in the loss of QuickBird-1.

The imagery of Quickbird can also be used as a backdrop for mapping applications, such as Google Earth and Google Maps.

Launch Window: 1851-1906 GMT (1451-1506 EDT) Launch Vehicle: Delta II Launch Site: SLC-2W, Vandenberg Air Force Base, California USAF Designation: Quickbird 2

Quick Bird I

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The first QuickBird was launched in November 2000, by EarthWatch from the Plesetsk Cosmodrome in Russia. QB-1 failed to reach planned orbit and was declared a failure.

Quick Bird-I Specifications

Criteria SpecificationSensors 60 cm (24 in) (1.37 μrad) panchromatic at nadir

2.4 m (7 ft 10 in) (5.47 μrad) multispectral at nadir

MS Channels: blue (450-520nm), green (520-600nm), red (630-690nm), near-IR (760-900nm)

Swath width and area size

Nominal swath width: 16.5 km at nadir Accessible ground swath: 544 km centered on the satellite

ground track (to 30° off nadir) Area of interest

o Single area: 16.5 km by 16.5 km

o Strip: 16.5 km by 165 km

Orbit Altitude: 450 km – 98 degree sun synchronous inclination Revisit frequency: 1 to 3.5 days depending on latitude at 60

cm resolution Viewing angle: Agile spacecraft, in-track and cross-track

pointing

Period 93.4 minutes

Features and Benefits

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Design and Specification

Design Specification

Launch Information Date: October 18, 2001Launch Window: 1851-1906 GMT (1451-1506 EDT)Launch Vehicle: Delta IILaunch Site: SLC-2W, Vandenberg Air Force Base, California

Orbit Altitude: 450 km, 98 degree, sun-synchronous inclinationRevisit frequency: 2-3 days depending on latitudeViewing angle: Agile spacecraft - in-track and cross-track pointingPeriod: 93.4 minutes

Per Orbit Collection ~128 gigabits (approximately 57 single area images)

Swath Width & Area Size

Nominal swath width: 16.5 kilometers at nadir Accessible ground swath: 544 km centered on the satellite ground track (to ~30° off-nadir) Areas of interest

Single Area: 16.5 km x 16.5 km

Strip: 16.5 km x 115 km

Metric Accuracy 23 meter circular error, 17 meter linear error (without ground control)

Sensor Resolution & Spectral

Panchromatic61 centimeter (2 ft) Ground Sample Distance (GSD) at nadir Black & White: 445 to 900 nanometers

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Bandwidth

Dynamic Range

ADCS Approach

Pointing and Agility

Onboard Storage

Spacecraft

5.2.2. WorldView-1

WorldView-1, launched September of 2007, is fast, agile and accurate. The high-capacity, panchromatic imaging system features half-meter resolution imagery.

Operating at an altitude of 496 kilometers, WorldView-1 has an average revisit time of 1.7 days and is capable of collecting up to 750,000 square kilometers (290,000 square miles) per day of half-meter imagery. The satellite is also equipped with state-of-the-art

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geolocation accuracy capabilities and exhibits stunning agility with rapid targeting and efficient in-track stereo collection.

Features and Benefits

Design and SpecificationsLaunch Information Date: September 18, 2007

Launch Vehicle: Delta 7920 (9 strap-ons)Launch Site: Vandenberg Air Force Base

Orbit Altitude: 496 kilometersType: Sun synchronous, 10:30 am descending nodePeriod: 94.6 minutes

Mission Life Expected end of life: 2018Spacecraft Size, Mass & Power 3.6 meters (12 feet) tall x 2.5 meters (8 feet) across,

7.1 meters (23 feet) across the deployed solar arrays2500 kilograms (5500 pounds)3.2 kW solar array, 100 Ahr battery

Sensor Bands PanchromaticSensor Resolution (GSD = Ground Sample Distance)

0.50 meters Ground Sample Distance (GSD) at nadir0.59 meters GSD at 25° off-nadir

Dynamic Range 11-bits per pixelTime Delay Integration (TDI) 6 selectable levels from 8 to 64Swath Width 17.6 kilometers at nadirAttitude Determination and 3-axis stabilized

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Control Actuators: Control Moment Gyros (CMGs)Sensors: Star trackers, solid state IRU, GPS

Pointing Accuracy & Knowledge Accuracy: < 500 meters at image start and stopKnowledge: Supports geolocation accuracy below

Retargeting Agility Acceleration: 2.5 deg/s/sRate: 4.5 deg/sTime to slew 300 kilometers: 10.5 seconds

Onboard Storage 2199 gigabits solid state with EDACCommunications Image and Ancillary Data: 800 Mbps X-band

Housekeeping: 4, 16 or 32 kbps real-time,                         524 kbps stored, X-bandCommand: 2 or 64 kbps S-band

Max Viewing Angle / Accessible Ground Swath

Nominally +/-45° off-nadir = 1,036 km wide swathHigher angles selectively available

Per Orbit Collection 331 gigabitsMax Contiguous AreaCollected in a Single Pass

60 x 110 km mono30 x 110 km stereo

Revisit Frequency 1.7 days at 1 meter GSD or less4.6 days at 25° off-nadir or less (0.59 meter GSD)

Geolocation Accuracy (CE 90) Specification of 6.5 m CE90 at nadir, with actual accuracy in the range of 4.0 - 5.5 m CE90 at nadir, excluding terrain and off-nadir effects With registration to GCPs in image : 2.0 meters.

5.2.3. Worldview-2

WorldView-2, anticipated to launch Sep/Oct, 2009, is the first 8-band multispectral satellite commercially available.

WorldView-2 Quick Stats

Resolution: 50 cm Swath Width: 16.4 kilometers at nadir

New Spectral Bands: coastal, yellow, red edge, Near-IR2

Collection Capacity: 975,000 sq km/day

Slew Time: 300 km in 9 seconds Average Revisit: 1.1 days

With a mission life of 7.25 years, and operating at an altitude of 770 km, the WorldView-2 system is expected to bring unsurpassed agility, capacity, accuracy and spectral diversity to commercial earth imaging.

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Features and Benefits

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1.3. GeoEye:

GeoEye Inc. (NASDAQ: GEOY) (formerly Orbital Imaging Corporation or ORBIMAGE) is a commercial satellite imagery company based in Dulles, Virginia[3]

that is the world's largest space imaging corporation.

The company was founded in 1992 as a division of Orbital Sciences Corporation in the wake of the 1992 Land Remote Sensing Policy Act which permitted private companies to enter the satellite imaging business. The division was spun off in 1997.

GeoEye again made history with the Sept. 6, 2008 launch of GeoEye-1—the world's highest resolution commercial earth-imaging satellite.

1.3.1. GeoEye-1

GeoEye-1 is equipped with the most sophisticated technology ever used in a commercial satellite system. It offers unprecedented spatial resolution by simultaneously acquiring 0.41-meter panchromatic and 1.65-meter multispectral imagery. The detail and geospatial accuracy of GeoEye-1 imagery further expands applications for satellite imagery in every commercial and government market sector.

The spacecraft is intended for a sun-synchronous orbit at an altitude of 425 miles (684 km) and an inclination of 98 degrees, with a 10:30 a.m. equator crossing time. GeoEye-1 can image up to 60 degrees off nadir. It is operated out of Dulles, Virginia and was built in Arizona by General Dynamics Advanced Information Systems.

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Spectral Bands: Panchromatic (Black and White) & Multispectral (Red, Green, Blue and NIR)

Resolution: Collected at 0.41-m Panchromatic & 1.65-m Multispectral; sold at 0.5-m Panchromatic & 2.0-m Multispectral due to US government regulations

Revisit Time: ~ 3 days (depends on latitude)

Positional Accuracy: 2.5-m CE90% (does not account for topographic distortions)

Swath Width: 15.2-km at nadir

Archive Dates: Late 2008 to Present

Stereo Availability: Archive (as available) and as new collections

Orbital Altitude: 681-km

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Key GeoEye-1 Specifications

1.3.2. GeoEye-2

GeoEye-2, which has a contract with ITT Corporation for the imaging is scheduled launch in 2011 or 2012 and has a planned resolution of 25 cm (9.8 in). GeoEye’s OrbView-2 collects on a daily basis color imagery of the Earth’s land and ocean surfaces.

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As the foundation upon which GeoEye built the SeaStarSM Fisheries Information Service, OrbView-2 provides imagery for maps used by commercial vessels to detect favorable oceanographic fishing conditions. The satellite also provides broad-area coverage in 2,800 km-wide swaths, which are routinely used in naval operations, environmental monitoring, and global crop-assessment applications.

6.0. Future Role of Remote Sensing

Remote sensing is a critical component of the geospatial toolset, particularly in this era of global impacts and global change. Remote sensing technologies enable us to bring together data on a global scale in order to study and analyze the intricate systems of our dynamic planet. Remote sensing will continue to increase in importance as our populations grow and our resources become scarcer.

The issue of sustainability is served well by the network of sensors that orbit our planet and send us calibrated and ongoing data about our resources, land use and impacts.

6.1. Global Coverage

The pace of remote sensing satellite launches will only increase as we realize the need to gain a better understanding on our dynamic planet. Remote sensing satellites provide an extremely valuable and unique scientific perspective, with the ability to cover wide areas to uncover broad change over time.

An increasing number of countries are also involved in remote sensing efforts. There are now well more than a dozen countries with satellites, including the United States, Russia, China, Canada, Israel, Italy, France, Egypt, Japan, India, Indonesia, Brazil, Argentina, Algeria, Nigeria, Morocco, South Korea, Turkey, Taiwan, the United Kingdom, Ukraine and the European Union.

6.2. Future Satellite Program

There are many different types of airborne sensing instruments at many different resolutions. For many purposes these days we’re looking for the greatest possible spatial resolution for our imagery so that even small features on the ground can be seen clearly and classified from space.

Future scientists will have an increasing number of sensors and measurements to study, with sensors that continue to adapt to the needs of the missions. Individual sensor inputs as well as multi-sensor arrays will gain orbit to provide valuable top-down data. Here some Future satellite programs are given:

6.3. Specification of future Satellite Program

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Family Satellite Organization Launch End

PROBA (Project for On-Board Autonomy)

Proba-V 01/03/2012

Earth Explorers EarthCARE 01/07/2011

EnMAP EnMAP 01/01/2012

GMES Sentinel missions Sentinel-2 01/11/2012

GMES Sentinel missions Sentinel-4 01/06/2017

GMES Sentinel missions Sentinel-3 01/11/2012

GMES Sentinel missions Sentinel-5 01/06/2019

Comparison among different satellite programs

Satellite features Geoeye-1 Ikonos QuickBird Corona Spot

Resolution .50-meter 1-meter 2.70-7.60 m

Spectral range (pan)

450-800 nm 526-929 nm

Blue 450-510 nm 445-516 nm 450 – 520 nanometers

Green 510-580 nm 505-595 nm 520 – 600 nanometers

Red 655-690 nm 632-698 nm 630 - 690 nanometers

Pan Resolution at nadir

.41 meters .82 meters 61 cm. (2 ft)

Multi-spectral Resolution at nadir

1.64 meters 3.28 meters

Swath width at nadir

15.2 km 11.3 km 16.5 km.

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Launch date 06-Sep-08 24-Sep-99 October 18, 2001

Life Cycle 7 years Over 8.5 years 1959-1962 1986-2002

Revisit Time 3 days at 40° latitude with elevation > 60°

3 days at 40° latitude with elevation > 60°

2-3 days depending on latitude

only 1 day 26 days

Orbital Altitude 681 km 681 km 450 km about 60,000 ft

832 kilometers

Nodal Crossing 10:30 AM 10:30 AM

Approximate Archive size (km2)

0 245,000,000 3600km2

References Campbell James B., Introduction to Remote Sensing. Gibson Paul J., Introduction to Remote Sensing; Principles and Concepts. Harris Ray, Satellite Remote Sensing; An introduction. Jensen John R., Remote Sensing of the Environment; An Earth Resource

Perspective. Gibson Paul J., Introduction to Remote Sensing; Principles and Concepts. Lillesand Thomas M. and Kiefer Ralph W., 1979. Remote Sensing and Image

Interpretation, John Wiley and Sons, Lnc, New York, Chicheter, Brisbane, Toronto, Singapure.

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