A 1,500-km scar from an ancient impact, brimming with clues to water.
Isidis Planitia is a giant impact basin roughly 1,500 km across, one of the largest and best-preserved on Mars. Its floor is a smooth plain of sediments, and its western rim hosts Jezero crater, where the Perseverance rover now hunts for signs of ancient life.
Claim your plot here →Isidis formed when a large asteroid or comet slammed into the boundary between Mars' ancient southern highlands and northern lowlands, gouging a basin some 1,500 km wide. Over time the floor filled with sediments and volcanic material, leaving a smooth plain dotted with mysterious mounds that may be mud volcanoes or eroded deposits.
The basin's greatest fame comes from its rim: Jezero crater, a former lake and river delta, sits on the northwestern edge and is now home to NASA's Perseverance rover collecting samples for future return to Earth. Isidis thus links a planet-scale impact to one of humanity's most focused searches for ancient Martian life.
Smaller than the vast Hellas basin but still one of Mars' great impact scars, over a thousand kilometers wide.
It dwarfs any impact structure on Earth — big enough to swallow entire mountain ranges.