United States:
* Mariner 4 (1964): First successful flyby of Mars, sending back the first close-up images.
* Mariner 6 and 7 (1969): Flybys that took more detailed images of the surface.
* Mariner 9 (1971): First spacecraft to orbit Mars, mapping a significant portion of the surface.
* Viking 1 and 2 (1976): Landed on the surface and conducted the first successful searches for life.
* Mars Pathfinder (1997): Deployed the Sojourner rover, which explored the surface.
* Mars Global Surveyor (1997-2006): Mapped the entire planet in high resolution and studied its atmosphere.
* Mars Odyssey (2001-present): Studying the Martian surface and subsurface, particularly looking for water ice.
* Spirit and Opportunity (2004-2010/2018): Rovers that explored the surface, providing evidence of past water activity.
* Mars Reconnaissance Orbiter (2006-present): Continues to study the surface, atmosphere, and geology of Mars.
* Phoenix (2008): Landed near the north pole and confirmed the presence of water ice beneath the surface.
* Curiosity (2012-present): Rover investigating the geology and habitability of the Gale Crater.
* InSight (2018-2022): Lander studying the interior structure of Mars.
* Perseverance (2021-present): Rover collecting rock samples for potential future return to Earth.
Soviet Union/Russia:
* Mars 1 (1962): First attempt to reach Mars but failed to communicate after a flyby.
* Mars 2 (1971): First spacecraft to reach Mars, but the lander crashed.
* Mars 3 (1971): First successful landing on Mars, but the lander only transmitted data for 20 seconds.
* Phobos 1 and 2 (1988): Missions to study the Martian moon Phobos, with Phobos 2 losing contact before reaching its target.
European Space Agency:
* Mars Express (2003-present): Orbiter studying the atmosphere, surface, and subsurface of Mars.
India:
* Mangalyaan (2014-present): Orbiter studying the Martian atmosphere, surface, and geology.
China:
* Tianwen-1 (2021-present): Orbiter, lander, and rover studying the surface and subsurface of Mars.
This list is not exhaustive but covers the most significant space probes that have visited Mars. There are also ongoing missions and future plans for robotic exploration of Mars from different space agencies around the world.
