(CNN) — Here’s a look at the exploration of Mars. The United States, Soviet Union and China are the only three countries to land a spacecraft on Mars. There have been nine successful US Mars landings: ...

Skylights, openings in the surface of Mars that descend down into caves, have been found on Mars, along with signatures for the presence of water ice. New images from the Mars Express orbiter reveal ...

Drone-mounted radar flown over glaciers on Earth show how the technology can map buried ice in detail, helping future Mars spacecraft choose exactly where to drill.