A formidable new radar satellite jointly developed by the United States and India is set to launch, designed to track subtle changes in Earth’s land and ice surfaces and help predict both natural and human-caused hazards.
Dubbed Nisar (NASA-ISRO Synthetic Aperture Radar), the pick-up truck-sized spacecraft is scheduled for lift-off from the Satish Dhawan Space Centre on India’s southeastern coast, riding an ISRO Geosynchronous Satellite Launch Vehicle rocket.
Highly anticipated by scientists, the mission has also been hailed as a milestone in growing US-India cooperation between President Donald Trump and Prime Minister Narendra Modi.
“Our planet surface undergoes constant and meaningful change,” Karen St Germain, director of Nasa’s Earth Science division, told reporters. “Some change happens slowly. Some happens abruptly. Some changes are large, while some are subtle.”
By picking up on tiny changes in the vertical movement of the Earth’s surface – as little as one centimetre – scientists will be able to detect the precusors for natural and human-caused disasters, from earthquakes, landsides and volcanoes to ageing infrastructure like dams and bridges.
“We’ll see land substance and swelling, movement, deformation and melting of mountain glaciers and ice sheets covering both Greenland and Antarctica, and of course, we’ll see wildfires,” added St Germain, calling Nisar “the most sophisticated radar we’ve ever built”.
Equipped with a 12m dish that will unfold in space, Nisar will record nearly all of Earth’s land and ice twice every 12 days from an altitude of 747km.
As it orbits, the satellite will continuously transmit microwaves and receive echoes from the surface. The returning signals are distorted – but computer processing will reassemble them into detailed images. — AFP
