NASA-ISRO Satellite Sends 1st Radar Images of Earth's Surface

Captured on Aug. 21, this image from NISAR’s L-band radar shows Maine’s Mount Desert Island. Green indicates forest; magenta represents hard or regular surfaces, like bare ground and buildings. The magenta area on the island’s northeast end is the town of Bar Harbor. (Credit: NASA/Pl-Caltech) 

The NASA-ISRO Synthetic Aperture Radar (NISAR) satellite has successfully transmitted its first radar images of Earth’s surface, marking a major milestone in the joint U.S.-India mission.

Highlights from the First Radar Images

• Mount Desert Island, Maine (Aug 21):
  • Captured using NASA’s L-band radar.
  • Forests appear green, water bodies in dark tones, and urban areas in magenta.
  • The town of Bar Harbor is clearly visible, showcasing the radar’s ability to distinguish land cover types.
• Forest River, North Dakota (Aug 23):
  • Shows wetlands, forests, and farmland with circular irrigation plots.
  • Differentiates fallow fields from active crops like corn and soybeans.

On Aug. 23, NISAR imaged land adjacent to northeastern North Dakota’s Forest River. Light-colored wetlands and forests line the river’s banks, while circular and rectangular plots throughout the image appear in shades that indicate the land may be pasture or cropland with corn or soy. (Credit: NASA/JPL-Caltech) 

What Makes NISAR Unique

• Dual Radar System: Combines NASA’s L-band with ISRO’s S-band for comprehensive Earth surface analysis.
• High Resolution: Can resolve features as small as 5 meters.
• Global Coverage: Orbits Earth every 12 days from 747 km altitude.

Applications

• Disaster response (e.g., landslides, floods, earthquakes)
• Agricultural monitoring and food security
• Climate change and ecosystem tracking
• Infrastructure and urban planning

Science operations begin November 2025. NISAR is set to revolutionize Earth observation and environmental monitoring.

Source – usembassy.gov

History & Timeline of NISAR, the World’s Most Expensive Earth-Imaging Satellite

The NASA-ISRO Synthetic Aperture Radar (NISAR) satellite is a collaborative project between NASA and ISRO, aimed at providing advanced radar imaging for Earth observation.

NISAR is expected to be the world's most expensive Earth-imaging satellite, with a total cost estimated at US$1.5 billion. The data collected will be freely available to the scientific community and the public, aiding in understanding and managing Earth's natural resources and hazards.

Here's a brief history and timeline of the NISAR mission:

Conceptualization

2014: The partnership between NASA and ISRO was formalized with the signing of a Memorandum of Understanding (MoU) to develop and launch the NISAR satellite.

2016: Detailed design and development work began, with both agencies contributing their expertise and resources.

Artist Rendering of NISAR (Source: NASA/ JPl-Caltech) 

Development and Testing

2018-2020: The development of the satellite's components, including the L-band radar provided by NASA and the S-band radar provided by ISRO, was completed.

2020-2023: Integration and testing of the satellite and its instruments were conducted to ensure functionality and reliability.

Launch Preparation

2023: The satellite was transported to the Satish Dhawan Space Centre in Andhra Pradesh, India, for final preparations and integration with the launch vehicle.

2024: Final checks and rehearsals were conducted in preparation for the scheduled launch in early 2025.

NISAR's flight antenna system undergoes thermal vacuum testing at NASA's Jet Propulsion Laboratory

Launch and Mission

March 2025 (Planned): The NISAR satellite is scheduled to be launched aboard ISRO's Geosynchronous Satellite Launch Vehicle Mark II (GSLV Mk II) from the Satish Dhawan Space Centre.

Mission Objectives

Earth Observation: NISAR will map the entire globe every 12 days, providing data on ecosystems, ice mass, vegetation, sea level rise, groundwater, and natural hazards like earthquakes, tsunamis, volcanoes, and landslides.

Dual Radar Systems: The satellite will carry both L-band and S-band radars, allowing for comprehensive monitoring of Earth's surface movements and natural processes.

NISAR Launch and Deploy Animation Video 

ISRO, NASA To Launch Joint Remote Sensing Satellite Early Next Year

The Indian Space Research Organization (ISRO) and the US space agency NASA plan to launch a joint remote sensing satellite for Earth observation in the first quarter of next year.

The Satellite named NASA-ISRO Synthetic Aperture Radar (NISAR) onboard ISRO’s GSLV will be launched in first quarter of 2024, said science and technology minister Dr. Jitendra Singh.

Dr. Singh met a high-level delegation of NASA led by its Administrator Bill Nelson.

A Low Earth Orbit (LEO) observatory Satellite, NISAR, once placed in the orbit, will provide data for understanding changes in Earth’s ecosystems, ice mass, vegetation
biomass, sea level rise, ground water and natural hazards, including earthquakes, tsunamis, volcanoes and landslides.

If every thing goes according to the plan, NISAR will observe nearly all of Earth’s land and ice surfaces twice every 12 days, measuring movements in extremely fine detail. It will also survey forests and agricultural regions to help scientists understand carbon exchange between plants and the atmosphere.

NISAR’s payload will be the most advanced radar system ever launched as part of a NASA science mission, and it will feature the largest-ever radar antenna of its kind: a drum-shaped, wire mesh reflector nearly 40 feet (12 meters) in diameter that will extend from a 30-foot (9-meter) boom.

Besides this, Nelson also urged the minister to expedite the programme related to India’s first astronaut aboard a NASA rocket to the International Space Station (ISS).

Nelson also met Rakesh Sharma, the first Indian to fly to space.

It was a great honor to speak with students in Bengaluru today with Rakesh Sharma, the first Indian to fly to space. His story lit up the room! To the Artemis Generation in India and beyond: Work hard, dream big, and reach for the stars. The universe is the limit! pic.twitter.com/mnPUJDfr8P

— Bill Nelson (@SenBillNelson) November 29, 2023

ISRO and NASA have formed a Joint Working Group (JWG) on Human spaceflight cooperation and are exploring cooperation in radiation impact studies, micro meteorite & orbital debris shield studies; space health and medicine aspects. The 8th meeting of India-USA Joint Working Group on Civil Space Cooperation (CSJWG) was held in Washington DC in January 2023.

ISRO/DoS is also in discussion with prominent US industries (like Boeing, Blue Origin & Voyager) on specific items of cooperation and also to explore joint collaborations with Indian commercial entities.

The Indian side informed that a concept paper on the Implementing Arrangement (IA) is under consideration between ISRO and NASA. After a few iterations, both sides arrived at a mutually agreed draft and the same is processed for intra-Governmental approvals.