JPL Scientist Leads Global Earth-Monitoring Breakthrough

A Pasadena scientist is leading a mission that will observe Earth like no mission before, as the National Aeronautics and Space Administration’s Jet Propulsion Laboratory prepares to launch its collaborative NISAR satellite with the Indian Space Research Organisation in the coming months. The mission marks the first time the two agencies have cooperated on hardware development for an Earth-observing mission. 

Paul Rosen, whose connection to the Jet Propulsion Laboratory began during his college years, reflects on his early days at the lab: “It also drew me to JPL in 1981 as a college student: I spent two summers analyzing data from the mission.” Now serving as Project Scientist, Rosen explains from the Jet Propulsion Laboratory’s Pasadena campus: “The planet’s surfaces never stop changing — in some ways small and subtle, and in other ways monumental and sudden. With NISAR, we’ll measure that change roughly every week, with each pixel capturing an area about half the size of a tennis court.” 

The satellite marks a historic technological achievement as the first Earth-observing satellite equipped with two types of radar. “NISAR will be the first Earth-observing satellite with two kinds of radar — an L-band system with a 10-inch (25-centimeter) wavelength and an S-band system with a 4-inch (10-centimeter) wavelength,” Rosen explains. “Whether microwaves reflect or penetrate an object depends on their wavelength. Shorter wavelengths are more sensitive to smaller objects such as leaves and rough surfaces, whereas longer wavelengths are more reactive with larger structures like boulders and tree trunks.” 

The dual-radar satellite will measure land deformation from earthquakes, landslides, and volcanoes, while tracking glaciers and ice sheets and monitoring forest and wetland changes to understand their impact on the global carbon cycle. The mission’s origins trace back to the National Aeronautics and Space Administration’s DESDynI proposal following the 2007 Decadal Survey by the National Academy of Sciences. At the time, the Indian Space Research Organisation was exploring launching an S-band satellite. The two science teams proposed a dual-band mission, leading to the 2014 partnership agreement. 

The California Institute of Technology-managed Jet Propulsion Laboratory leads the U.S. component, providing the L-band radar system, radar reflector antenna, deployable boom, high-rate communication subsystem for science data, GPS receivers, solid-state recorder, and payload data subsystem. The Indian Space Research Organisation’s Space Applications Centre

Ahmedabad, the lead center for payload development, provides the S-band radar instrument. The U R Rao Satellite Centre in Bengaluru leads the Indian Space Research Organisation components, with the launch vehicle coming from the Vikram Sarabhai Space Centre. 

Since the partnership began, the agencies have been collaborating across more than 9,000 miles (14,500 kilometers) and 13 time zones. “Given the volume of the data, NASA decided that it would be processed and stored in the cloud, where it’ll be free to access,” Rosen notes. The National Remote Sensing Centre in Hyderabad will handle S-band data reception and operational products generation. Hardware development has spanned continents, with components built in different countries before final assembly in India. As Rosen observes of this unprecedented collaboration: “It’s been a long journey — literally.”