As it flew by Mars, the spacecraft's onboard camera snapped 22 pictures of the planet's surface, sending them back home to Earth – the first-ever close-up photos of Mars obtained by humans, and the very first photos of another planet obtained from a position in deep space.

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

Mars has lost immense amounts of water over it lifetime, and scientists aren't sure exactly how. New research hints that the planet's violently varying tilt may be a key factor.

Two meteorites found in the Sahara in 2023 might be from Mercury, a study suggests, but doubts remain due to how little is known about the planet closest to the sun.

Sheel and his team found that when the atmosphere of Mars is laden with dust, the atmosphere becomes less conductive, prohibiting the flow of charges. This could cause a massive charge buildup in a dust-filled vortex, triggering lightning, he explains.

New research shows how Mars may have undone its own habitability, while Earth stayed stable enough to support life.

Dark “slope streaks,” likely resulting from dust avalanches, stretch across an area of Mars called Acheron Fossae in this image from the High-Resolution Imaging Science Experiment (HiRISE) camera aboard NASA’s Mars Reconnaissance Orbiter.