Final answer:
The Hellas Basin is the deepest depression on the surface of Mars, deeper than the Valles Marineris canyons. Knowledge of Martian geology derives mainly from space missions that have analyzed the planet's surface and meteorites. The Valles Marineris is extensive but not the deepest, with the Hellas Basin being deeper.
Step-by-step explanation:
The deepest depression found on the surface of Mars is the Hellas Basin of Mars. While the Valles Marineris canyon system is the most well-known and extensive crack on the Martian surface, it is not the deepest. Valles Marineris, compared to the Grand Canyon on Earth, provides a stark illustration of Mars' significant geological depth and complexity.
The Valles Marineris system extends for about 5000 kilometers and reaches depths of approximately 7 to 8 kilometers. However, the Hellas Basin, a giant impact crater in the southern hemisphere of Mars, holds the title for the deepest depression at about 7 to 9 kilometers deep and over 2200 kilometers in diameter.
Most of our knowledge about Martian topography and geology comes from highly successful orbiters, landers, and rovers, along with the study of a few Martian rocks that have reached Earth as meteorites. The Martian landscape offers a rich history of geological activity, including tectonic features, significant erosion, and the presence of what were likely vast amounts of water in the past.
The Tharsis bulge is a prominent feature on Mars and showcases some of the largest volcanic mountains in the solar system, including Olympus Mons, while the Valles Marineris canyons exemplify tectonic forces at work. To explore this fascinating terrain, Mars missions continue to select landing sites that provide insights into these extensive geological features.