EARTH OBSERVATION SATELLITES (EOS)
1. Context
ISRO’s latest Earth Observation Satellite ‘EOS-08’ launched by the Small Satellite Launch Vehicle (SSLV)-D3 today at 9:17 hrs from Satish Dhawan Space Centre, Shriharikota.The primary objectives of the EOS-08 mission include designing and developing a microsatellite, creating payload instruments compatible with the microsatellite bus, and incorporating new technologies required for future operational satellites.
2.What is Earth observation satellites?
- Earth observation satellites, also known as Earth remote sensing satellites, are designed to monitor and collect data about the Earth from orbit. This category includes both military spy satellites and those intended for non-military purposes, such as environmental monitoring, weather forecasting, cartography, and more.
- These satellites are crucial for overseeing and safeguarding our environment, managing resources, responding to global humanitarian crises, and supporting sustainable development. They offer valuable insights into various aspects like ocean salinity, ice thickness, crop health, and air quality.
- The most common type of Earth observation satellites are Earth-imaging satellites, which capture images similar to aerial photographs. However, some EO satellites conduct remote sensing without creating images, such as those using GNSS radio occultation techniques
3.Types of Earth Observation Satellites
Earth observation satellites are crucial tools for monitoring our planet. They provide valuable data for various applications, including weather forecasting, environmental monitoring, and disaster management
Earth observation (EO) satellites can be categorized into two main types depending on their imaging techniques: passive and active.
-
Passive Satellites: These satellites detect radiation that is reflected off the Earth's surface, including visible light and infrared. They generally cannot operate effectively through cloud cover.
-
Active Satellites: These satellites emit energy towards the Earth's surface and measure the reflected signal to gather information. They are capable of penetrating cloud cover to obtain data
4. How do earth observation satellites collect data?
- Earth observation satellites operate in various orbits, providing different viewpoints of the Earth. Due to constraints in power and storage, most satellites do not continuously collect data.
- Some satellites provide consistent and reliable data, while others gather it intermittently over time.
- The collected data is stored on the satellite until it can be transmitted to a ground station when it comes into view.
- The duration from image capture to data availability can range from a month to just a few minutes, with advancements in technology reducing this time.
- As multiple companies own these satellites, there are various data providers with distinct pricing models.
- ISRO has deployed numerous operational remote sensing satellites. Currently, thirteen of these satellites are in sun-synchronous orbits, while four are in geostationary orbits.
- The data collected from these satellites supports a range of applications including agriculture, water resources, urban planning, rural development, mineral exploration, environmental monitoring, forestry, ocean resource management, and disaster response
5. Advantages of low Earth satellites
Earth observation satellites offer numerous advantages across various fields due to their ability to collect and transmit data from space.
Here are some of the key benefits:
- Climate Change: Track changes in climate patterns, ice melt, sea level rise, and greenhouse gas concentrations.
- Natural Disasters: Monitor and assess the impact of natural disasters like hurricanes, earthquakes, and floods in real-time.
- Agriculture: Provide data on crop health, soil conditions, and irrigation needs, helping optimize agricultural practices and increase yields.
- Water Resources: Monitor water bodies, track changes in water availability, and manage water resources more effectively.
- Land Use: Assist in urban planning and land use management by providing detailed imagery and data on land development and changes.
- Infrastructure: Support infrastructure development by providing accurate and up-to-date information on land and environmental conditions
|
For Prelims: LOS, PSLV, GSLV
For Mains: GS III - Science & technology
|
|
Previous Year Questions
1. With reference to India's satellite launch vehicles, consider the following statements: (UPSC 2018)
1. PSLVs launch satellites useful for Earth resources monitoring whereas GSLVs are designed mainly to launch communication satellites.
2. Satellites launched by PSLV appear to remain permanently fixed in the same position in the sky, as viewed from a particular location on Earth.
3. GSLV Mk III is a four- staged launch vehicle with the first and third stages using solid rocket motors; and the second and fourth stages using liquid rocket engines.
Which of the statements given above is/are correct?
A. 1 only
B. 2 and 3
C. 1 and 2
D. 3 only
Answer: A
|
Source: PIB, Business Standard
