Remote Sensing and Geographic Information Systems (GIS) is part of Space Technology. Below are notes on 15 sub-topics, followed by practice MCQs from State PSC and UPSC papers.

Applications of Remote Sensing and GIS in various sectors (e.g., Urban Planning, Agriculture, Disaster Management, Environmental Monitoring)

Disaster

Management,

Environmental Monitoring)

  • Bhoonidhi Vista: A data visualization service of Bhoonidhi, providing full resolution mosaicked data visualization via Web Map Service (WMS).
  • Bhoonidhi Vista: Enabled for ResourceSat-2/2A, Sentinel 1, and Sentinel 2 satellites.
  • Earth Observation Satellites / Remote Sensing applications: Urban planning, Mineral prospecting, Ocean resources management, Disaster management, Assessment of crop productivity, Locating groundwater resources, Traffic studies.
  • Department of Space (DoS) / ISRO signed an MoU with geospatial technology company CE Info Systems Pvt. Ltd. (MapmyIndia).
  • The DoS-MapmyIndia collaboration aims to build holistic geospatial solutions by utilizing Earth Observation datasets, NavIC, Web Services, and APIs from MapmyIndia, integrating with ISRO's existing geospatial platforms like Bhuvan, VEDAS, and MOSDAC. (Note:

Satellite-based systems providing autonomous geospatial positioning with global/ regional coverage.

GPS (Global Positioning System)

USA, global.

    • GLONASS

(Globalnaya

Sputnikovaya

Sistema) Russia, global.

Galileo

European Union, global.

    • BeiDou

Satellite

System (BDS) China, global.

System) India, regional.

QZSS (Quasi-Zenith Satellite System)

Japan, regional.

Satellite Network

Operates via a constellation of Earthorbiting satellites transmitting radio signals.

Positioning Principle

Based on

trilateration/ranging, measuring distances from a receiver to multiple satellites to calculate position. Requires minimum four satellites for 3D position and time.

position. Requires minimum four

satellites for 3D position and time.

    • Output GPS receivers provide precise location in terms of

latitude, longitude, and altitude (3D coordinates) and accurate time.

    • Applications

Dual-use system

– originally

developed for military operations,

but now extensively used for

diverse civilian purposes (e.g.,

disaster management, timing), thus

not exclusively for military

operations.

    • Segments Comprises Space Segment (satellites), Control Segment (ground stations), and User Segment (receivers).

Remote Sensing

Provides accurate ground control points (GCPs) for georeferencing satellite imagery and aerial photographs, improving their spatial accuracy.

    • GIS Acts as a primary data source for collecting new spatial data (points, lines, polygons) in the field, updating existing GIS databases, and enabling realtime location tracking and asset management within GIS environments.

Principles and Fundamentals of Remote Sensing

  • Indian Institute of Remote Sensing (IIRS) is a constituent unit of ISRO.
  • National Remote Sensing Centre (NRSC), formerly NRSA, is located in Hyderabad.
  • Remote sensing employs various sensors/ technologies, including: Electromagnetic sensors, Multi-Spectral Scanners, Radar, and Microwave Sensors.

Remote Sensing Data Acquisition, Pre-processing, and Image Interpretation

  • LANDSAT satellites are in Sun-synchronous orbits, allowing data acquisition at the same local time.
  • For LANDSAT, data for an adjacent area to its west (non-overlapping swath) becomes available after a certain number of days (its repeat cycle, e.g., 16 days) at the same local time.
  • India's first operational remote sensing satellite was IRS-1A, launched in 1988.
  • IRS-1A was launched from Baikonur Cosmodrome (then in USSR, now Kazakhstan).
  • The Indian Remote Sensing (IRS) satellite series is specifically used for Earth observation, including Land Use/Land Cover (LULC) mapping.
  • ISRO's primary launch site is the Satish Dhawan Space Centre (SDSC) at Sriharikota, Andhra Pradesh.
  • Cartosat-3 was launched by ISRO from Sriharikota in November 2019.
  • EOS-01 (Earth Observation Satellite-01), previously named RISAT-2BR2, was launched by ISRO from Sriharikota in November 2020.
  • The SuperView-1 series of remote sensing satellites is operated by China.

Remote Sensing Platforms and Sensors (Active and Passive sensors)

  • Remote Sensing Platforms: Satellites (e.g., LEO, GEO), aircraft, drones.
  • Passive Sensors: Detect naturally available energy (e.g., reflected sunlight, emitted thermal radiation). Require external illumination (e.g., sun). Examples: Optical cameras, thermal infrared scanners.
  • Active Sensors: Provide their own energy source (e.g., electromagnetic pulses) and measure backscattered signal. Operate day/

4. Space Applications in Communication, Meteorology, Agriculture, and Disaster

Management

Practice MCQs: Remote Sensing and Geographic Information Systems (GIS)

Applications of Remote Sensing and GIS in various sectors (e.g., Urban Planning, Agriculture, Disaster Management, Environmental Monitoring)

  1. Consider the following statements regarding Bhoonidhi Vista :

    Asked in: UPSC CDS 1 2024

    1. 1 only
    2. 2 only
    3. Both 1 and 2
    4. Neither 1 nor 2
    Show answer

    Answer: A. 1 only

    It is a data visualisation service of Bhoonidhi providing full resolution mosaicked data visualisation capability through Web Map Service. It is enabled for ResourceSat-2/2A, Sentinel 1 and 2 satellites. Which of the statements given above is/are correct? Statement 1 is correct: Bhoonidhi is ISRO's Earth Observation Data Dissemination portal. Bhoonidhi Vista is a service under Bhoonidhi that provides visualization capabilities for geospatial data, including full-resolution mosaicked data, often accessible via Web Map Service (WMS). Statement 2 is correct: ISRO/NRSC processes and provides data from its own ResourceSat series of satellites (ResourceSat-2/2A) and also serves as a dissemination node for European Space Agency's Copernicus data, including from Sentinel-1 and Sentinel-2 satellites. Bhoonidhi and its visualization tools like Vista are enabled to handle and display data from these diverse sources.

  2. Which of the following are the applications of Earth Observation Satellites? Urban planning 1. Mineral prospecting 2. Ocean resources management 3. Disaster management. 4. Select the correct answer code:

    Asked in: GPSC Prelims CSP 2 2024

    1. 1, 2, 3
    2. 1, 3, 4
    3. 2, 3, 4
    4. 1, 2, 3, 4
    Show answer

    Answer: D. 1, 2, 3, 4

    - Earth Observation Satellites collect data about the Earth's physical, chemical, and biological systems. -

  3. Urban planning: Satellites provide data on land use, urban sprawl, infrastructure, and environmental conditions in urban areas. - 2. Mineral prospecting: Remote sensing data helps identify geological features, rock types, and surface anomalies associated with mineral deposits. - 3. Ocean resources management: Satellites monitor ocean parameters like temperature, colour (phytoplankton), currents, pollution, and support fisheries management. - 4. Disaster management: Satellites are crucial for monitoring natural disasters like floods, fires, earthquakes, and volcanic eruptions, assessing damage, and aiding relief efforts. 3. Consider the following statements: The Department of Space (DoS), under which ISRO comes, has signed an MoU with geospatial technology company CE Info Systems Pvt. Ltd. The collaboration will enable them to jointly identify and build a holistic geospatial portal utilising earth observation datasets, ‘NavIC’, Web Services and APIs (application programming interface) available in MapmyIndia. The geospatial portals will be called ‘Bhuvan’, ‘VEDAS’ and ‘MOSDAC’.

    Asked in: GPSC Prelims CSP 2 2023

    1. only 1 is correct
    2. only 2 is correct
    3. both 1 and 2 are not correct
    4. both 1 and 2 are correct
    Show answer

    Answer: A. only 1 is correct

    Statement 1 is correct. The Department of Space (DoS), which oversees ISRO, did sign an MoU with CE Info Systems Pvt. Ltd. (MapmyIndia) for collaboration on geospatial services. Statement 2 is incorrect. While the collaboration involves leveraging earth observation datasets, NavIC, and data/ services from ISRO's existing portals like ‘Bhuvan’, ‘VEDAS’, and ‘MOSDAC’ along with MapmyIndia's resources, the statement incorrectly claims that "The geospatial portals will be called ‘Bhuvan’, ‘VEDAS’ and ‘MOSDAC’." These are existing ISRO portals, and the collaboration aims to integrate data/services for a combined platform or application, not rename or create new portals with these names as the outcome of the collaboration.

  4. Indian Institute of Remote Sensing (IIRS) is situated at :

    Asked in: UKPSC CS Prelims 2012

    1. Dehradun
    2. New Delhi
    3. Lucknow
    4. Nagpur
    Show answer

    Answer: A. Dehradun

    The Indian Institute of Remote Sensing (IIRS), a constituent unit of the Indian Space Research Organisation (ISRO), is located in Dehradun, Uttarakhand.

  5. In which of the following activities are Indian Remote Sensing (IRS) satellites used? Assessment of crop productivity 1. Locating groundwater resources 2. Mineral exploration 3. Telecommunications 4. Traffic studies 5. Select the correct answer using the code given below.

    Asked in: UPSC IAS 2015

    1. 1, 2 and 3 only
    2. 4 and 5 only
    3. 1 and 2 only
    4. 1, 2, 3, 4 and 5
    Show answer

    Answer: A. 1, 2 and 3 only

    Indian Remote Sensing satellites are designed for monitoring and mapping the Earth's resources and environment. Their applications include agriculture, water resources, forestry, geology, land use mapping, disaster management, and urban studies.

  6. GAIL (India) Limited in the last week of November, 2015 launched which portal for monitoring the pipeline Right of Use (ROU) through Space Technology?

    Asked in: WBPSC CS Prelims 2016

    1. Bhuvan-GAIL Portal
    2. GEO-Store Portal
    3. K & J Satellite Portal
    4. Star one C 2 Portal
    Show answer

    Answer: A. Bhuvan-GAIL Portal

    The portal was developed in collaboration with the Indian Space Research Organisation (ISRO) using ISRO's geoportals, Bhuvan and RISAT (Radar Imaging Satellite). It provides real-time or near real- time satellite imagery and GIS tools to monitor the pipeline corridor for encroachments, construction activities, and other potential threats, ensuring the safety and integrity of the pipelines.

  7. ‘Bhuvan’ is

    Asked in: preliminary paper tcs tps 2020

    1. a mini satellite launched by ISRO for promot‐ ing the distance education in India
    2. the name given to the next moon Impact Probe, for Chandrayan II
    3. a geoportal of ISRO with 3D imaging capabilities of India
    4. a space telescope developed by India
    Show answer

    Answer: C. a geoportal of ISRO with 3D imaging capabilities of India

    Bhuvan is ISRO's geoportal offering 3D imaging of India.

  1. Which one of the following statements with respect to Global Positioning System (GPS) is not correct?

    Asked in: UPSC NDA 1 2022

    1. It is based on network of satellites orbiting above the Earth.
    2. It is based on the system of triangulation.
    3. GPS receivers provide location in terms of latitude, longitude and altitude.
    4. It provides information exclusively for military operations.
    Show answer

    Answer: D. It provides information exclusively for military operations.

    Let's evaluate each statement: A) It is based on network of satellites orbiting above the Earth. Correct. GPS relies on a constellation of dozens of satellites maintained by the United States. B) It is based on the system of triangulation. Correct. GPS receivers calculate their position by determining the distance from multiple satellites. This process of determining location based on distance measurements from known points is often referred to as trilateration, which is similar in concept to triangulation (which uses angles). C) GPS receivers provide location in terms of latitude, longitude and altitude. Correct. GPS provides a 3D position fix, including latitude, longitude, and height above a reference ellipsoid. D) It provides information exclusively for military operations. Incorrect. While GPS was developed and is maintained by the U.S. military (Department of Defense), it has been available for civilian use globally since the 1980s and is used extensively for navigation, mapping, surveying, timing, etc., by both military and civilian users.

Principles and Fundamentals of Remote Sensing

  1. What is the Indian Institute of Remote Sensing part of ?

    Asked in: MPSC CS Prelims 2012

    1. ISRO
    2. GSI
    3. DAE
    4. CSIR
    Show answer

    Answer: A. ISRO

    The Indian Institute of Remote Sensing (IIRS), located in Dehradun, is a premier institute for research, training, and education in remote sensing and geoinformatics. It is a constituent unit of the Indian Space Research Organisation (ISRO).

  2. Which of the following is not used for remote sensing?

    Asked in: Asst. Town Planner 2022

    1. Multi-Spectral Scanner
    2. Radar
    3. Microwave Sensors
    4. Electromagnetic sensors
    Show answer

    Answer: D. Electromagnetic sensors

    Multi-spectral scanners, radar, and microwave sensors are used in remote sensing. "Electromagnetic sensors" is not a standard classification for a specific sensor type in this field.

  3. Itemcode : GK1105 Q105: National remote sensing agency is located at -

    Asked in: Asstt. Jailor 2013

    1. Ahmadabad
    2. Bengaluru
    3. Hyderabad
    4. Sriharikota
    Show answer

    Answer: C. Hyderabad

    Location of the National Remote Sensing Agency/ Centre.

Remote Sensing Data Acquisition, Pre-processing, and Image Interpretation

  1. If LANDSAT data for an area is received today, then the data for an adjacent area to its west will be available

    Asked in: JPSC CS Prelims 2014 · JPSC CS Prelims 2015

    1. in the next orbit of the satellite on the same day
    2. next day at the same local time
    3. after certain number of days at the same local time
    4. after a variable controllable time
    Show answer

    Answer: C. after certain number of days at the same local time

    To image an adjacent area to the west, the satellite needs to complete a certain number of orbits and days until its ground track moves sufficiently westward to cover that specific area. This takes a specific number of days, known as the satellite's repeat cycle (e.g., 16 days for many LANDSAT missions), to revisit or cover adjacent areas within its full swath coverage pattern. The data will be available for the adjacent area at the same local time due to the sun-synchronous nature of the orbit.

  2. ISRO launched Cartosat-3 recently from

    Asked in: WBPSC CS Prelims 2020

    1. Sriharikota
    2. Baleswar
    3. Ahmedabad
    4. Trombay
    Show answer

    Answer: A. Sriharikota

    ISRO launches most of its satellites, including the Cartosat series, from the Satish Dhawan Space Centre (SDSC) located at Sriharikota, Andhra Pradesh. This is India's primary spaceport for satellite launches.

  3. India's First remote sensing satellite (I.R.S.-1A) was launched from :

    Asked in: UPPCS Prelims 1994

    1. Baikonour
    2. Cape Kennedy
    3. French Guiana
    4. Sri Harikota
    Show answer

    Answer: A. Baikonour

    India's first operational remote sensing satellite, IRS-1A, was launched on March 17, 1988. It was launched by the Soviet Union using a Vostok rocket from the Baikonur Cosmodrome.

  4. The pair of SuperView -1 remote sensing satellites were launched by

    Asked in: APPSC Group II Prelims 2016

    1. USA
    2. Russia
    3. France
    4. China
    Show answer

    Answer: D. China

    The SuperView-1 satellites are designed for commercial imaging services, providing high-resolution imagery for various applications including mapping, urban planning, disaster monitoring, and agriculture.

  5. What is the name of the latest earth observation satellite launched by ISRO (November 2020) along with 9 international customer satellites from Andhra Pradesh?

    Asked in: WBCS Main Paper 4 2021

    1. G Sat-30
    2. India Sat
    3. EOS-1
    4. EOS-2
    Show answer

    Answer: C. EOS-1

    The Indian Space Research Organisation (ISRO) successfully launched its Earth Observation Satellite (EOS-01) along with nine international customer satellites onboard the PSLV-C49 rocket from the Satish Dhawan Space Centre (SDSC) in Sriharikota, Andhra Pradesh, on November 7, 2020. EOS-01 is a radar imaging satellite intended for applications in agriculture, forestry, and disaster management support.

  6. Which of the following series of Indian satellites is used for LULC mapping?

    Asked in: WBCS Main Paper 3 2022

    1. LANDSAT
    2. METEOSAT
    3. IRS
    4. INSAT
    Show answer

    Answer: C. IRS

    - IRS satellites are the primary Indian satellites for remote sensing applications. - LULC mapping is a key application area for remote sensing data provided by satellites like IRS.

  7. In the year 1988, India launched the first remote sensing satellite, ________.

    Asked in: WBCS Main Paper 3 2019

    1. IRS-1A
    2. INSAT-1D
    3. INSAT-1A
    4. None of the above
    Show answer

    Answer: A. IRS-1A

    IRS-1A marked India's entry into the field of space- based remote sensing, which is used for resource monitoring and management.

Remote Sensing Platforms and Sensors (Active and Passive sensors)

  1. Consider the following statements : (i) NISAR is a low Earth orbit observatory being jointly developed by ISRO and NASA. (ii) NISAR is a low Earth orbit observatory being jointly developed by ISRO and European Space Agency. (iii) The objective of NISAR is to co-develop and launch a dual frequency synthetic aperture RADAR on an Earth observation satellite. (iv) NISAR is planned to be launched in 2024. Select the correct statements using the codes given below.

    Asked in: APSC CCE Prelims Exam 2023

    1. (i) and (iii) only
    2. (ii) and (iii) only
    3. (i) and (iv) only
    4. (i), (iii) and (iv) only
    Show answer

    Answer: D. (i), (iii) and (iv) only

    NISAR (NASA-ISRO Synthetic Aperture Radar) is a joint Earth observation mission between NASA (USA) and ISRO (India) (i). Its objective is to co- develop and launch a satellite carrying a dual- frequency (L-band and S-band) Synthetic Aperture Radar (SAR) for monitoring Earth's surface changes (iii). The mission is planned for launch in 2024 (iv).

  2. CARTOSAT- 1 & 2, RISAT - 1 & 3 and SARAL are

    Asked in: KPSC KAS Prelims 2014

    1. Student Satellites
    2. Communication Satellites
    3. Navigation Satellites
    4. Earth observation Satellites
    Show answer

    Answer: D. Earth observation Satellites

    - Earth observation satellites collect data about the Earth's physical, chemical, and biological systems. - Remote sensing satellites (like CARTOSAT, RISAT) and satellites for environmental or oceanographic monitoring (like SARAL) fall under the category of Earth observation. - Communication satellites relay signals, Navigation satellites are used for positioning, and Student satellites are small satellites often built by universities for educational or research purposes.

  3. Which of the following satellites is the first Earth observation satellite made in Ethiopia ?

    Asked in: KPSC KAS Prelims 2017

    1. ETRSS-1
    2. ETISAT-1
    3. ETSARS-1
    4. ETHIOS-1
    Show answer

    Answer: A. ETRSS-1

    ETRSS-1 (Ethiopian Remote Sensing Satellite 1) was successfully launched into space in December

  4. It was designed to collect data for weather forecasting, agriculture, and environmental monitoring. 22. Name of the recently launched first satellite of Ethiopia is

    Asked in: KPSC KAS Prelims 2017

    1. ETRSS-1
    2. ETISAT-1
    3. ETSARS-1
    4. ETHIOS-1
    Show answer

    Answer: A. ETRSS-1

    Ethiopia launched its first Earth observation satellite, ETRSS-1, in December 2019.