The new images by the Curiosity rover on Mars show "dramatic evidence" of ancient groundwater in crisscrossing low ridges, ...

Mariner 4, built by JPL in Pasadena, took the images on July 14, 1965. One of the mission's leaders reflects on decades of ...

Mars' opposition occurs about every two years and coincides with the planet's retrograde motion, which began on Dec. 7 and will end Feb. 23. Retrograde occurs when a planet appears to be moving ...

Mars orbits at an average distance of 142 million miles (228 million km) from the sun. Its orbit is about 1.5 times the size of Earth's. Sunlight takes about 13 minutes to get to Mars, while it ...