Nisar: The billion-dollar radar that can see through clouds and darkness
The mission's open-source data will be freely available to researchers. (Photo: Isro)
WHAT MAKES NISAR A GAME-CHANGER?
At its heart, Nisar carries a world-first technology – a dual-frequency Synthetic Aperture Radar (SAR). Most radar imaging satellites work with a single frequency, but Nisar carries two powerful radar systems: L-band radar (24 cm wavelength) built by Nasa and S-band radar (12 cm wavelength) developed by Isro.This unique combination allows Nisar to 'see' through clouds, thick forest canopies, smoke, and even in complete darkness.More importantly, it can detect tiny changes in the Earth's surface, as small as a few millimeters. That means scientists can track how much a glacier has shifted, how much a fault line has moved after an earthquake, or even how much a city is sinking due to groundwater depletion.
Nisar is set to become something more – a guardian that can sense Earth's heartbeat. (Photo: Nasa)
Nisar achieves this precision through a special technique called Interferometric Synthetic Aperture Radar (InSAR). Think of it like taking two radar 'photos' of the same place a few days apart and comparing them to spot tiny differences.Nisar sends out invisible radar waves to Earth's surface and listens for the waves that bounce back. By carefully analysing the timing (or 'phase') of these returning waves, InSAR can detect changes as small as a centimeter, like the ground shifting slightly after an earthquake or a glacier moving over time.advertisementThis creates detailed maps showing how Earth's surface is changing, helping scientists predict disasters or monitor climate shifts with incredible accuracy, no matter the weather or time of day.All this data is made possible thanks to its massive 12-meter gold-plated deployable mesh antenna – the largest radar imaging antenna ever launched into space. For comparison, it's almost as wide as a badminton court when fully unfolded.
WHY THE WORLD NEEDS NISAREarth's rapid changes are outpacing the capabilities of traditional satellites, which often lack the precision needed to capture critical details. Nisar bridges this gap with its high-resolution, all-weather, day-and-night imaging, delivering a near real-time view of our planet's dynamic systems.It will revolutionise our understanding by:advertisementTracking climate change: Observing polar ice loss, glacier shifts, and permafrost thawing with unprecedented accuracy.Disaster management: Identifying subtle signs of land subsidence, landslide risks, and fault-line movements to predict earthquakes early.Agriculture & water security: Forecasting crop yields, monitoring soil moisture, and mapping groundwater depletion to ensure resource sustainability.Forests & ecosystems: Measuring deforestation, forest biomass, and the carbon storage potential of vegetation to support conservation efforts.In simple terms, Nisar will give us a near-real-time 'health check-up' of the Earth every few days.
It has the largest radar imaging antenna ever launched into space. (Photo: Nasa)
A BILLION-DOLLAR PARTNERSHIPNisar is one of the most expensive Earth observation missions ever undertaken, with a total cost estimated at $1.5 billion (Rs 12,500 crore).Nasa's contribution, covering the L-band radar, radar electronics, GPS receivers, and engineering support, is approximately $1.2 billion (Rs 10,000 crore).Isro's contribution, which includes the S-band radar, satellite bus, launch vehicle, and ground systems, is around Rs 788 crore (approximately $93 million).Despite the significant investment, the mission's open-source data will be freely available to researchers and governments worldwide, offering immense value for global scientific and climate research efforts. THE ROAD AHEADFor decades, satellites have been our eyes in the sky, but Nisar is set to become something more – a guardian that can sense Earth's heartbeat.By tracking movements invisible to the naked eye, it promises to help humanity understand natural hazards, prepare for disasters, and fight climate change.advertisementWhen it finally unfurls its giant golden antenna in orbit, Nisar will mark not just a triumph of space technology but also a symbol of international cooperation for the planet's future.(This is an authored article by Manish Purohit. Manish is a solar energy and spacecraft solar panel expert with extensive experience in managing critical space missions, including Chandrayaan-2 and Mangalyaan)- EndsMust Watch
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News18
11 minutes ago
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Rocket Politics: How India Turned A Geopolitical Roadblock Into NISAR's Launchpad
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Rocket politics began with a denial; it ends with an engine built in Bengaluru lifting a joint mission with the very nation that tried to keep it grounded. top videos View all And in that arc lies the true power of Indian science, not just to reach the stars, but to rewrite the politics that guard the gates to them. The writer is a technocrat, political analyst, and author. He pens national, geopolitical, and social issues. His social media handle is @prosenjitnth. Views expressed in the above piece are personal and solely those of the author. They do not necessarily reflect News18's views. About the Author Prosenjit Nath The writer is an Indian technocrat, political analyst, and author. tags : ISRO nasa Satellite Launch view comments Location : New Delhi, India, India First Published: July 30, 2025, 13:21 IST News opinion Opinion | Rocket Politics: How India Turned A Geopolitical Roadblock Into NISAR's Launchpad Disclaimer: Comments reflect users' views, not News18's. Please keep discussions respectful and constructive. Abusive, defamatory, or illegal comments will be removed. News18 may disable any comment at its discretion. By posting, you agree to our Terms of Use and Privacy Policy.
United News of India
14 minutes ago
- United News of India
ISRO-NASA joint satellite NISAR set for launch today from Sriharikota
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News18
an hour ago
- News18
NISAR AT A GLANCE
Agency: PTI Sriharikota (Andhra Pradesh), July 30 (PTI) As ISRO is set to launch the NISAR satellite onboard a GSLV-F16 rocket later on Wednesday, here are some of the significant highlights of the satellite jointly developed with US' NASA. Some of the highlights of the mission •In September, 2014, NASA and ISRO sign agreement to launch a joint Earth Observing Satellite Mission. •NISAR (NASA-ISRO Synthetic Aperture Radar) mission marks the first collaboration between the two top space agencies on a project of this scale and marks the next step in Earth-observing mission. •It becomes first satellite mission between the two space agencies for the use of double L-band and S-band radar frequencies to measure changes on the Earth's surface less than a centimeter across. •NASA would provide L-band Synthetic Aperture Radar, a high rate communication subsystem for science data, GPS receivers while ISRO would provide spacecraft bus, the S-band radar and the launch vehicle, GSLV-F16. •NISAR satellite would provide a 3D-view of Earth's land and ice. It would continuously monitor earthquake and landslide prone areas and determine how quickly glaciers and ice sheets are changing. •Data from NISAR would provide critical insights to help governments and decision makers for natural and human caused hazards. •It would measure the woody biomass and its changes, track changes in the extent of active crops, understand the changes in wetlands extent. • Map Greenland's & Antarctica's ice sheets, dynamics of sea ice and mountain glaciers. • Characterise land surface deformation related to seismicity, volcanism, landslides, and subsidence and uplift associated with changes in subsurface aquifers, hydrocarbon reservoirs. •NISAR is the most advanced radar system every launched by NASA or ISRO. It would generate more data on a daily basis than from any previous Earth satellite missions. • GSLV-F16 becomes the first launch vehicle for ISRO to launch an earth observation satellite in a Sun-synchronous Polar Orbit (SSPO). •The GSLV-F16/NISAR is the 102nd mission from Sriharikota. •The first 90 days after the launch would be dedicated to commissioning of the satellite in order to prepare the observatory for science VIJ SA view comments First Published: July 30, 2025, 12:30 IST Disclaimer: Comments reflect users' views, not News18's. Please keep discussions respectful and constructive. Abusive, defamatory, or illegal comments will be removed. News18 may disable any comment at its discretion. By posting, you agree to our Terms of Use and Privacy Policy.
