Meridiani Planum is a plain located 2 degrees south of Mars's equator, in the westernmost portion of Sinus Meridiani. It hosts a rare occurrence of gray crystalline hematite. On Earth, hematite is often formed in hot springs or in standing pools of water; therefore, many scientists believe that the hematite at Meridiani Planum may be indicative of ancient hot springs or that the environment contained liquid water. The hematite is part of a layered sedimentary rock formation about 200 to 800 meters thick. Other features of Meridiani Planum include volcanic basalt and impact craters.
Sinus Meridiani is an albedo feature on Mars stretching east-west just south of the planet's equator. It was named by the French astronomer Camille Flammarion in the late 1870s.
Endurance is an impact crater lying situated within the Margaritifer Sinus quadrangle (MC-19) region of the planet Mars. This crater was visited by the Opportunity rover from May until December 2004. Mission scientists named the crater after the ship Endurance that sailed to the Antarctic through the Weddell Sea during the ill-fated 1914-1917 Imperial Trans-Antarctic Expedition, considered to be the last expedition of the Heroic Age of Antarctic Exploration organized by Ernest Shackleton.
Eagle is a 22-metre long impact crater located on the Meridiani Planum extraterrestrial plain, situated within the Margaritifer Sinus quadrangle (MC-19) portion of the planet Mars. The Opportunity rover came to rest inside Eagle crater when it landed in 2004. Scientists were delighted that the rover landed there, as the crater contains rocky outcroppings that helped prove that Meridiani was once an ocean floor.
Martian spherules are the abundant spherical hematite inclusions discovered by the Mars rover Opportunity at Meridiani Planum on the planet Mars in 2004.
Heat Shield Rock is a basketball-sized iron-nickel meteorite found on the Meridiani Planum plain of Mars by the Mars rover Opportunity in January 2005.
Bounce Rock is a football-sized primarily pyroxene rock found within the Margaritifer Sinus quadrangle (MC-19) region of the planet Mars. It was discovered and observed by the Mars Exploration Rover Opportunity in April 2004. The rock was named for it having been struck by Opportunity as the craft bounced to a stop during its landing stage.
The geology of Mars is the scientific study of the surface, crust, and interior of the planet Mars. It emphasizes the composition, structure, history, and physical processes that shape the planet. It is analogous to the field of terrestrial geology. In planetary science, the term geology is used in its broadest sense to mean the study of the solid parts of planets and moons. The term incorporates aspects of geophysics, geochemistry, mineralogy, geodesy, and cartography. A neologism, areology, from the Greek word Arēs (Mars), sometimes appears as a synonym for Mars's geology in the popular media and works of science fiction. The term areology is also used in the subreddit "r/Areology" and the Areological Society.
The Margaritifer Sinus quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Margaritifer Sinus quadrangle is also referred to as MC-19. The Margaritifer Sinus quadrangle covers the area from 0° to 45° west longitude and 0° to 30° south latitude on Mars. Margaritifer Sinus quadrangle contains Margaritifer Terra and parts of Xanthe Terra, Noachis Terra, Arabia Terra, and Meridiani Planum.
Almost all water on Mars today exists as ice, though it also exists in small quantities as vapor in the atmosphere. What was thought to be low-volume liquid brines in shallow Martian soil, also called recurrent slope lineae, may be grains of flowing sand and dust slipping downhill to make dark streaks. The only place where water ice is visible at the surface is at the north polar ice cap. Abundant water ice is also present beneath the permanent carbon dioxide ice cap at the Martian south pole and in the shallow subsurface at more temperate conditions. More than 5 million km3 of ice have been detected at or near the surface of Mars, enough to cover the whole planet to a depth of 35 meters (115 ft). Even more ice is likely to be locked away in the deep subsurface.
Endeavour is an impact crater located in the Meridiani Planum extraterrestrial plain within the Margaritifer Sinus quadrangle (MC-19) region of the planet Mars. Endeavour is about 22 kilometers (14 mi) in diameter. Using Mars Reconnaissance Orbiter data, phyllosilicate-bearing outcrops have been detected along its rim. These minerals may have formed under wet conditions in a low-acidic environment during the early history of Mars. There are raised rim segments to the north, east, and southwest. The rim has become worn, rounded and degraded, with infilling of plains material in a manner similar to the Victoria crater.
Mars may contain ores that would be very useful to potential colonists. The abundance of volcanic features together with widespread cratering are strong evidence for a variety of ores. While nothing may be found on Mars that would justify the high cost of transport to Earth, the more ores that future colonists can obtain from Mars, the easier it would be to build colonies there.
Oileán Ruaidh is a rock discovered on Mars in September 2010 by the Opportunity rover. It is a 45 centimeter wide dark rock that is thought to be an iron meteorite. It was given the name Oileán Ruaidh after the Irish language name of Oileán Ruaidh island in County Donegal in Ireland.
During past ages, there was rain and snow on Mars; especially in the Noachian and early Hesperian epochs. Some moisture entered the ground and formed aquifers. That is, the water went into the ground, seeped down until it reached a formation that would not allow it to penetrate further. Water then accumulated forming a saturated layer. Deep aquifers may still exist.
The composition of Mars covers the branch of the geology of Mars that describes the make-up of the planet Mars.
Shelter Island meteorite was found on Mars by the Opportunity rover on October 1, 2009. It is about 27 centimetres (11 in) long.
Block Island meteorite, officially named Meridiani Planum 006 shortened as MP 006, was found on Mars by the Opportunity rover on July 17, 2009. It is about 67 centimetres (26 in) across.
Opportunity is a robotic rover that was active on the planet Mars from 2004 to 2018. Launched on July 7, 2003, Opportunity landed on Mars' Meridiani Planum on January 25, 2004 at 05:05 Ground UTC, three weeks after its twin Spirit (MER-A), also part of NASA's Mars Exploration Rover Mission, touched down on the other side of the planet. While Spirit became immobile in 2009 and ceased communications in 2010, Opportunity exceeded its planned 90 sol duration of activity by 17 years, 254 days. Opportunity continued to move, gather scientific observations, and report back to Earth until 2018. What follows is a summary of events during its continuing mission.
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