NISAR Radar Image Shows Bird-Shaped Feature on Antarctic Nunatak

Radar data from the NASA-ISRO Synthetic Aperture Radar (NISAR) satellite displayed a striking, bird-shaped pattern over East Antarctica. The “bird” is an optical illusion; the dark central area corresponds to the summit of Nunatak Zaterjavshijsja, while the apparent tail is a glacier-fed ice stream flowing toward the ocean and the “feathers” are deep crevasses radiating from the mountaintop. The processed image was released to the public on July 20, marking the first open-access distribution of NISAR’s radar observations.

NASA's NISAR satellite Antarctica image captures a giant bird-like shape hidden in East Antarctica's ice; here's what the colourful radar view means Space.com

NISAR, a joint Earth-observation mission of NASA and the Indian Space Research Organisation (ISRO), carries L-band and S-band synthetic-aperture radars capable of penetrating snow and ice. Launched in 2025, the satellite was designed to monitor land-surface changes, including ice-sheet dynamics, by measuring how polarized microwave signals bounce back from the terrain.

NASA's NISAR satellite Antarctica image captures a giant bird-like shape hidden in East Antarctica's ice; here's what the colourful radar view means Space.com

NASA explains that the image’s false-color scheme reflects how different polarizations interact with the ice. Magenta highlights smoother ice surfaces where horizontally polarized signals are reflected; green marks areas where vertically polarized signals either penetrate the snow or scatter off uneven features such as crevasses; white indicates a strong return of both polarizations, denoting mixed surface characteristics. Signal-analysis engineer Seongsu Jeong of NASA’s Jet Propulsion Laboratory noted that these color distinctions reveal glacier movement patterns and internal ice properties that are invisible to optical sensors.

NASA's NISAR satellite Antarctica image captures a giant bird-like shape hidden in East Antarctica's ice; here's what the colourful radar view means

By seeing through clouds, darkness, and surface snow, NISAR’s radar data enable researchers to track ice-sheet flow, assess stress on glacial terrain, and improve models of sea-level rise. The public release of these data expands access for scientists worldwide, supporting studies of climate-related hazards such as ice-sheet instability, earthquakes, landslides, and floods.

NASA's NISAR satellite Antarctica image captures a giant bird-like shape hidden in East Antarctica's ice; here's what the colourful radar view means