Mars

Unlike the other planets in the solar system, Mars is distinctly triaxial, meaning it is an ellipsoid with different sizes along all three axes.

Newly released images of Mars reveal a "smiley" salt deposit on the Red Planet's surface. A related study suggests that similar deposits, which were left behind from ancient lakes, may be a good place to look for signs of former life on Mars.

Astronomers have traced the origins of 200 meteorites to five impact craters in two volcanic regions on Mars, known as Tharsis and Elysium.

Scientists examining data from NASA's InSight Lander have revealed the likely presence of an underground reservoir containing enough liquid to cover the planet with a mile of water.

This stunning image of dune fields near Mars' north polar ice cap, taken by NASA's Mars Reconnaissance Orbiter, showcases the impact of polar winds on the Red Planet's landscape.

A peculiar leopard-spotted rock, found beside an ancient, dried-out river in Mars' Jezero crater, contains some tantalizing clues of ancient life, NASA said.

NASA's Curiosity rover revealed an 'oasis' of rare elemental sulfur on Mars after accidentally crushing a rock with its tires. The yellow crystals have never been spotted on the Red Planet before.

Four volunteers exited a mock Mars habitat at NASA's Johnson Space Center on July 6, bringing the agency's first year-long simulated Red Planet mission to an end.

New photos from the European Space Agency's Mars Express orbiter give us our best look yet at a giant ravine on the Red Planet. The dark "scar" was likely birthed by a gigantic blob of magma hidden beneath a massive nearby volcano millions of years ago.