When we think of ice on Mars, we typically think of the poles, where we can see it visibly through probes and even ground-based telescopes. But the poles are hard to access, and even more so given the restrictions on exploration there due to potential biological contamination. Scientists have long hoped to find water closer to the equator, making it more accessible to human explorers. There are parts of the mid-latitudes of Mars that appear to be glaciers covered by thick layers of dust and rock.