NISAR is the first satellite mission to collect radar data in two microwave bandwidth regions, called the L-band and the S-band, to measure changes in our planet's surface less than a centimeter across. This allows the mission to observe a wide range of Earth processes, from the flow rates of glaciers and ice sheets to the dynamics of earthquakes and volcanoes.
NISAR uses a sophisticated information-processing technique known as synthetic aperture radar to produce extremely high-resolution images. Radar penetrates clouds and darkness, enabling NISAR to collect data day and night in any weather. The instrument's imaging swath — the width of the strip of data collected along the length of the orbit track — is greater than 150 miles (240 kilometers), which allows it to image the entire Earth in 12 days.
Over the course of multiple orbits, the radar images will allow users to track changes in croplands and hazard sites, as well as to monitor ongoing crises such as volcanic eruptions. The images will be detailed enough to show local changes and broad enough to measure regional trends. As the mission continues for years, the data will allow for better understanding of the causes and consequences of land surface changes, increasing our ability to manage resources and prepare for and cope with global change.
NISAR is planned to launch in 2022 from India’s Satish Dhawan Space Center in Sriharikota, India, into a near-polar orbit. NASA requires a minimum of three years of global science operations with the L-band radar, and ISRO requires five years of operations with the S-band radar over specified target areas in India and the Southern Ocean.
All NISAR science data, L-band and S-band, will be freely available and open to the public, consistent with the long-standing NASA Earth Science open data policy. NASA has chosen the Alaska Satellite Facility Distributed Active Archive Center (DAAC) to host the mission’s data and products.