Recent studies about Mars reveal significant new insights into the planet's past habitability and water presence. A study from NYU Abu Dhabi suggests that underground water reservoirs persisted much longer than previously thought, even after surface water dried up around 3.7 to 4.2 billion years ago. Analysis of data from NASA's Curiosity rover, focusing on lithified sand dunes in Gale Crater, indicates that these formations were shaped by rising groundwater, which left behind mineral deposits like gypsum that can preserve organic molecules, making them prime targets for future astrobiological investigations. Meanwhile, new radar data from the Mars Reconnaissance Orbiter challenges earlier interpretations of liquid water under the south polar ice cap. The SHARAD radar signals, intensified through special maneuvers, show that the reflective signals previously thought to indicate a subsurface lake are more consistent with smooth, rocky or dusty layers rather than liquid water. This casts doubt on the existence of a liquid underground lake at the south pole, although the possibility remains open. Additionally, researchers have identified water-formed caves in the Hebrus Valles region, which could have served as protected habitats for microbial life in the past. These findings suggest that Mars may have had a long, transitional period of habitability, with underground environments offering refuge from harsh surface conditions. While the presence of water and habitable niches does not confirm life, these discoveries significantly refine the search areas for biosignatures and inform future exploration strategies.