World's most expensive Indo-US joint sat mission NISAR to lift off on July 30

NEW DELHI: The world’s most expensive earth observation satellite, NISAR, which has been jointly developed by Nasa and Isro, will be launched after much delay from the Sriharikota spaceport at 5.40 pm on July 30, the Indian space agency has said.
Both India and the US have been working on the NASA-ISRO SAR Mission (NISAR) for over a decade and it has cost them over $1.5 billion.

“Historic Launch Ahead... NISAR will scan the entire globe every 12 days, providing high-resolution, all-weather, day-and-night data. It can detect even subtle changes in Earth’s surface like ground deformation, ice sheet shifts, and vegetation dynamics,” Isro posted on X.
Talking to TOI on Tuesday, space minister Jitendra Singh said, “NISAR will open a new horizon in Indo-US collaboration. The satellite will take images of every piece of Earth. It will not only have scientific applications but also provide new earth science”.

The minister, who wanted to witness the crucial launch but may not be able to go to Sriharikota due to Parliament being in session, told TOI that “crucial data generated from NISAR will, besides being beneficial for the US and India, help other countries in disaster management. Thus, it will live up to PM Modi’s dream of Bharat playing the role of Vishwa Bandhu.”

India’s GSLV-F16 rocket will inject the synthetic aperture radar satellite into a 743-km sun-synchronous orbit with an inclination of 98.4 degrees. NISAR will observe Earth with a swath of 242 km and high spatial resolution, using SweepSAR technology for the first time. The satellite, weighing 2,392 kg, will be the first one to observe the Earth with a dual frequency synthetic aperture radar, with one each provided by Isro (S-band) and Nasa (L-band).

The NISAR mission is designed to observe and measure some of the planet’s most complex natural processes, including ecosystem disturbances and natural hazards such as earthquakes, tsunamis, volcanoes and landslides. The mission will also observe sea ice characteristics on the seas surrounding India’s Antarctic polar stations and can be used to detect a marine oil spill and disseminate the spill location for preventive measures. Its other applications include ship detection, shoreline monitoring, storm characterisation, changes in soil moisture, mapping & monitoring of surface water resources and disaster response. Data from the NISAR satellite will also be used to map crop growth, track plant health and monitor soil moisture — offering detailed, timely information for decision-making.

Under the terms of the agreement, Nasa has provided the mission's L-band synthetic aperture radar (SAR), a high-rate telecommunication subsystem for scientific data GPS receivers, a solid-state recorder, and a payload data subsystem. On the other hand, Isro has provided the satellite bus, an S-band synthetic aperture radar (SAR), launch vehicle GSLV-1F16, and associated launch services.
Two synthetic aperture radars aboard NISAR will detect changes in the planet’s surface down to fractions of an inch. The spacecraft will bounce microwave signals off Earth’s surface and receive the return signals on a radar antenna reflector measuring 39 feet across. It will also offer unprecedented coverage of Antarctica, information that will help with the study of how the continent’s ice sheet changes over time.

All data from NISAR will be freely available one to two days after observation and within hours in case of emergencies like natural disasters. Its data will also reveal information about the evolution and state of Earth's crust, help scientists better understand our planet's natural processes and changing climate, and aid future resource and hazard management.