A fresh re-examination of data collected by the Indian Space Research Organisation's (ISRO) Chandrayaan-1 spacecraft has led researchers to propose the possible detection of one of the oldest impact basins on the Moon — a finding that could rewrite aspects of our understanding of the solar system's violent earliest epochs.
The spacecraft, launched in October 2008, was India's pioneering lunar exploration mission. Although it ceased operations in August 2009 after just ten months due to a technical anomaly, the rich dataset it gathered has continued to yield scientific discoveries years later as analysts apply improved methods to its observations.
The newly identified feature appears to be an enormous circular depression carved into the lunar crust billions of years ago, likely formed when a massive celestial body struck the Moon during the period astronomers call the Late Heavy Bombardment — an era roughly 4.1 to 3.8 billion years ago when the inner solar system was pelted by asteroids and comet debris at extraordinary rates.
If confirmed through further study and cross-referencing with samples or data from other missions, this basin would rank alongside or potentially exceed the South Pole-Aitken basin in southern lunar hemisphere as one of the oldest and deepest impact structures known. The South Pole-Aitken basin itself measures approximately 2,500 kilometres across and is believed to be around 4.2 to 4.3 billion years old.
Scientists say such ancient impact basins serve as crucial time capsules. By studying their depth, composition, and structural characteristics, researchers can reconstruct the conditions of the early solar system, including the frequency and size of objects bombarding the Earth and Moon during their formative years.
ISRO has not yet issued an official statement regarding the finding, which appears to stem from academic analysis rather than a formal mission announcement. Experts note that Chandrayaan-1 carried several scientific instruments, including a moon mineralogy mapper and a high-energy gamma-ray and neutron spectrometer, both of which were instrumental in enabling detailed subsurface and compositional analyses that make such discoveries possible.
The potential identification underscores how legacy data from retired spacecraft continues to generate value long after their operational lifespans end, and it adds to growing international interest in revisiting archived lunar measurements with modern computational tools.
