Martian water ice is the presence of water ice on the planet Mars. It has been detected in various locations on the planet's surface, including near the poles and beneath the surface. The presence of water ice on Mars is important for studying the potential for past or present habitability on the planet, as well as for future human exploration missions. Scientists are continuing to study Martian water ice to understand its distribution, composition, and implications for potential future use in sustaining human life on Mars.