NISAR mission enters critical 90-day commissioning phase

After the commissioning is complete, the radars will be activated and it will start collecting data over 'all ice, all land, all the time' from the Earth.

Chennai: The historic NISAR mission, a landmark collaboration between NASA and ISRO, has entered its crucial 90-day commissioning phase, during which scientists will carry out rigorous checks, calibrations and orbital adjustments to prepare the satellite for full-scale earth observation.

The critical phase follows the successful launch of the radar imaging satellite on July 30 aboard a GSLV-F16 rocket from Srikharikota in Andhra Pradesh.

Speaking to PTI, Gerald W Bawden, Program Manager for Natural Hazards Research at NASA's Earth Sciences Division, outlined the key activities underway.

"NISAR is inserted at an altitude of 737 km and we need to actually rise up to 747 km and it will take about 45-50 days for those operations to take place," he explained.

After the commissioning is complete, he said the radars will be activated and it will start collecting data over "all ice, all land, all the time" from the Earth.

"The resolution will be 5 metres by 5 metres and we will be imaging that every 12 days. So it is a lot of data. It is more data that NASA has collected in any other mission."

On the key lessons from the collaboration with the Bengaluru-based space agency for the NISAR mission, the scientist said, NASA learned from the ISRO's focus on how science can help society, while ISRO gained from NASA's deep focus on scientific research.

Bawden said the project brought together scientists from two countries on opposite sides of the world, with a 12.5-hour time difference.

"... we had culture differences and the other thing is that we are on the opposite side of the world. We have to work together and we have the common love for technology."

"The two scientists (of ISRO and NASA) are building partnerships by working together, friendships. This NISAR partnership is more than building an amazing satellite, it is teams that are together to solve bigger problems," he noted.

Responding to a query on the opportunities the collaboration with ISRO offers for NASA, NASA Earth Sciences Division Program Executive Sanghamitra B Dutta said, "This is the first large earth observing misison that India and the United States have put together. India is also working on this human space flight. So there are collaborations between the US and India on this over the last 4-5 years."

"An Indian astronaut (Subhanshu Shukla) recently went to the International Space Station that has also been built as part of a collaboration between the US and India. We are enormously proud to work with each other and it will come in future in the commercial area, space collaboration and technology development, science area," she said.

Regarding the mission's dual-band radar, Dutta said radar missions have happened in the past.

"But simultaneous observation (of the Earth) in two different frequencies by two different radars flying together did not happen before. Scientists need not confine to the boundary of a country and they always discuss possibilities of new missions and bigger and better science," she said.

During discussions, Dutta said scientists from ISRO and NASA came up with the idea to fly two Radars at once, using two different frequencies to collect more data in different technical ways.

"The idea was first discussed between Space Applications Centre, ISRO Ahmedabad and scientists from Jet Propulsion Laboratory, NASA. They discussed, brainstormed and came up with the idea of two radars working simultaneously."

Supporting Dutta's statement, Bawden said there are major benefits of having two frequencies.

"We have technology challenge, and at the end of the day, we are building the technology to address scientific questions and NASA has the long L Band while ISRO has S band. It is fantastic to study agriculture like how corn grows, soya beans grow."