Mars could have been habitable much longer, study finds

It has long been accepted in the scientific community that Mars once had flowing water and a denser atmosphere. However, how long Mars remained habitable has been debated for years. A new study suggests this period may have been much longer than previously thought.

Scientists from New York University Abu Dhabi (NYUAD) in the United Arab Emirates have found evidence that ancient sand dunes in Gale Crater, billions of years ago, interacted with underground water and transformed into rock formations.

The findings indicate that Mars may have had habitable conditions much later than previously believed.

The study, published in the Journal of Geophysical Research – Planets, was led by Dimitra Atri from NYUAD's Center for Astrophysics and Space Sciences.

The team examined fossilized sand dunes in the Stimson Formation (SF) of Gale Crater observed by the Curiosity rover. Considering the crater's extremely arid conditions, these structures are believed to have formed during major water floods in the Noachian Period (around 4.1–3.7 billion years ago).

Researchers compared their findings with similar rock formations in the desert regions of the UAE, shaped by underground water. This comparison showed that the SF was influenced by groundwater at a later stage, leaving behind minerals such as calcium sulfate (gypsum), which are also found in Earth's deserts.

Similar results were obtained last year by the same research team at the Mars Conference in California, based on data from the Greenheugh Pediments region. Scientists argue that such fossilized structures could have preserved traces of microorganisms in the past, making them critical in the search for life. On Earth, sandstone deposits contain fossil traces of the oldest known microorganisms.

Experts recommend that these areas of Gale Crater be prioritized in future Mars missions. The study provides new clues about how Mars evolved into its extremely cold and dry current state, while showing that the planet once had habitable conditions for a much longer period.

This research offers renewed hope for scientists continuing the search for life on Mars.