India-U.S. Satellite Captures Antarctic Landscape Resembling a Hummingbird
Washington–A joint India-U.S. Earth observation satellite has begun releasing data from both of its radar instruments, giving scientists a new way to track changes across the planet and revealing an Antarctic landscape that resembles a hummingbird.
Public access to data from the NASA-ISRO Synthetic Aperture Radar satellite, known as NISAR, opened July 20. Teams in India and the United States will continue releasing processed data from the satellite’s L-band and S-band radar systems, NASA said.
The information can help researchers monitor the movement of land and ice, study forests and wetlands, and respond to natural hazards including earthquakes, landslides and floods.
The data release comes shortly before the first anniversary of NISAR’s launch from India’s Satish Dhawan Space Centre on July 30, 2025.
Since the launch, mission teams have calibrated the satellite’s instruments, refined data-processing systems and monitored nearly all of Earth’s land and ice-covered surfaces twice every 12 days.
NASA released an early image Tuesday showing Nunatak Zaterjavshijsja, a mountaintop in East Antarctica surrounded by ice flowing northeast toward the ocean. The fractured ice around the mountain creates an outline resembling a hummingbird.
As the glacier moves around the mountain, the terrain places stress on the ice. Deep crevasses appear as sharp green lines in the radar image, while smoother ice surfaces appear magenta.
“First, it’s a beautiful image, with rich details of features that provide insights to how the glacier is moving. Then, because radar can often see through snow and deep into the ice, NISAR can observe fundamentally different properties of Antarctic ice than can be seen in optical imagery,” said Seongsu Jeong, a signal analysis engineer at NASA’s Jet Propulsion Laboratory who produced the image.
“With NISAR we’re seeing what’s hidden beneath the surface,” he added.
The image was created using L-band measurements collected in August 2025 while U.S. and Indian teams were testing the satellite’s systems.
Its colors show how polarized microwave signals interacted with the ice. Horizontally polarized signals, generally associated with smoother surfaces, appear magenta. Vertically polarized signals may have partly penetrated the snow and ice or scattered from irregular features such as crevasse walls, producing green areas.
White areas may represent a strong combination of both types of radar scattering.
The Indian Space Research Organization’s Space Applications Centre in Ahmedabad has begun releasing S-band data through the Bhoonidhi portal. The U.S. side has started continuously releasing calibrated L-band products collected since June 17.
Earlier releases included sample products in January and thousands of preliminary products in February.
NISAR produces dozens of terabytes of scientific data each day and scans Earth from near the South Pole to 77.5 degrees north, above the Arctic Circle.
Its 39-foot, drum-shaped reflector is the largest radar antenna reflector NASA has sent into space.
NISAR is the first satellite jointly developed by NASA and ISRO. The mission builds on years of civil space cooperation between India and the United States, including NASA instruments carried aboard India’s Chandrayaan-1 lunar mission.
Unlike conventional optical instruments, synthetic aperture radar can collect observations through clouds and darkness. The technology is used to detect gradual surface movement and rapid changes caused by earthquakes, floods, landslides and other natural events. (Source: IANS)
