Marspedia

Explora el conocimiento del planeta rojo.

Términos totales: 250

Ablation (Heat Shield)

Technology & Instruments
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Ablation (Heat Shield)

The process by which a heat shield's material burns away and disintegrates in a controlled manner during atmospheric entry (EDL). This disintegration dissipates the immense heat energy generated by friction, protecting the spacecraft.

Acidalia Planitia

Planetary Science & Geology
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Acidalia Planitia

A large plain in the northern hemisphere, part of the lowlands. It is a site of high scientific interest due to a high concentration of subsurface water ice, detected by the Mars Odyssey orbiter.

Extravehicular Activity (EVA)

Human Exploration & Life Support
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Extravehicular Activity (EVA)

Any activity performed by an astronaut outside the protection of a spacecraft or planetary habitat. On Mars, an EVA will require advanced spacesuits that protect against low pressure, extreme temperatures, and radiation.

AEGIS (Rover Autonomy)

Technology & Instruments
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AEGIS (Rover Autonomy)

Acronym for "Autonomous Exploration for Gathering Increased Science". The AI software used by the Curiosity and Perseverance rovers. It allows the rover to autonomously identify interesting rock targets and fire its laser (ChemCam/SuperCam) at them without waiting for commands from Earth.

Aerobraking

Technology & Instruments
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Aerobraking

A space maneuver that uses a planet's atmospheric drag to slow down a spacecraft and adjust its orbit. It is a key technique for inserting orbiters into low science orbits at Mars without expending large amounts of propellant.

Aeroponics

Human Exploration & Life Support
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Aeroponics

A soilless plant-growing technique where roots are suspended in the air and misted with a fine spray of water and nutrients. It is a key life-support technology for future food production on Mars due to its extremely high water-use efficiency.

Controlled-Environment Agriculture (CEA)

Human Exploration & Life Support
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Controlled-Environment Agriculture (CEA)

The umbrella term for food-growing systems (including hydroponics and aeroponics) within a closed habitat. It involves total control over light, temperature, humidity, and nutrients to maximize crop yield and reliability on Mars.

Airbags (Landing System)

Technology & Instruments
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Airbags (Landing System)

A landing system used by the Mars Pathfinder (Sojourner) and MER (Spirit, Opportunity) missions. The lander, cocooned in giant airbags, bounced on the surface until it came to a stop. It is an effective method only for relatively lightweight payloads.

Isolation and Confinement

Human Exploration & Life Support
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Isolation and Confinement

One of the primary psychosocial risks of human exploration. It refers to the stress, anxiety, and interpersonal conflicts that arise from living in a small, enclosed space, far from Earth, with no possibility of quick escape, for months or years.

Alba Mons (Alba Patera)

Planetary Science & Geology
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Alba Mons (Alba Patera)

A unique type of shield volcano. While not extremely tall (only ~6.8 km), it is the largest volcano in the Solar System in terms of area (its base is the size of the United States). It features extremely long, low-slope lava flows.

Albedo

Planetary Science & Geology
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Albedo

A measure of the reflectivity of a surface. A low albedo (dark) absorbs more solar radiation, while a high albedo (bright, like polar caps) reflects it. It is a key factor in the Martian climate model.

ALH 84001

Planetary Science & Geology
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ALH 84001

A famous Martian meteorite found in Antarctica. In 1996, a team of scientists announced it contained structures (carbonate shapes and possible microfossils) that could be evidence of ancient microbial life, sparking major controversy and revitalizing astrobiology.

Amazonis Planitia

Planetary Science & Geology
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Amazonis Planitia

A very low-elevation plain and one of the smoothest surfaces on Mars. It is the type locality for the Amazonian Period (Mars's most recent geological period) and is covered in young lavas.

Mars Analogue

Planetary Science & Geology
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Mars Analogue

A location on Earth that shares geological, mineralogical, or environmental similarities with Mars (e.g., Atacama Desert in Chile, Devon Island in the Arctic). These sites are used to test instruments, rovers, and human mission protocols.

Crustal Magnetic Anomalies

Planetary Science & Geology
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Crustal Magnetic Anomalies

Strongly magnetized regions of the Martian crust, primarily in the southern hemisphere. They are the remnants of the global magnetic field that Mars had in its youth. They represent a form of paleomagnetism.

Apoapsis (Apoareion)

Technology & Instruments
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Apoapsis (Apoareion)

The point in an elliptical orbit around a body (Mars) where the spacecraft is farthest from the planet. (The Mars-specific term is Areoapsis or Apoareion).

Arabia Terra

Planetary Science & Geology
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Arabia Terra

A vast region in the northern hemisphere representing some of the oldest highlands on Mars. It is heavily cratered but at a much lower elevation than the southern highlands. It is a key region for studying early Mars.

Arcadia Planitia

Planetary Science & Geology
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Arcadia Planitia

A plain in the northern lowlands of Mars. It is a region of interest for future human missions due to the confirmed presence of abundant subsurface water ice glaciers near the surface.

Ares Vallis

Missions & Programs
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Ares Vallis

A large outflow channel that drains into Chryse Planitia. It was carved by catastrophic water floods in the past. The Mars Pathfinder mission (with the Sojourner rover) landed at its mouth in 1997.

Argyre Planitia

Planetary Science & Geology
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Argyre Planitia

One of the largest and best-preserved impact basins on Mars. It is the second-largest impact basin after Hellas. It is thought to have hosted a large lake in the past and features glacial characteristics.

Mission Architecture

Technology & Instruments
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Mission Architecture

The complete conceptual plan for an exploration campaign. It defines all elements: launch vehicles, trajectory, transit spacecraft, habitats, resupply missions, crew size, and scientific objectives.

Arsia Mons

Planetary Science & Geology
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Arsia Mons

The southernmost shield volcano of the three Tharsis Montes volcanoes (along with Pavonis and Ascraeus Mons). It is notable for seasonal cloud activity (an orographic "cloud cone") that forms over its caldera.

Ascraeus Mons

Planetary Science & Geology
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Ascraeus Mons

The northernmost and tallest of the three "Tharsis Montes" volcanoes. It is a shield volcano with a complex caldera and numerous lava flows.

Gravity Assist

Technology & Instruments
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Gravity Assist

An orbital maneuver that uses the gravity of a planet or other massive body to alter a spacecraft's speed and trajectory. It is a fundamental technique in interplanetary navigation to save propellant and reduce travel time.

Astrobiology

Planetary Science & Geology
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Astrobiology

The scientific discipline that studies the origin, evolution, distribution, and future of life in the universe, including the search for extraterrestrial life, both on Mars and other celestial bodies.

Propulsive Landing

Technology & Instruments
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Propulsive Landing

A landing technique (used by Viking, Phoenix, and in the final stages by Curiosity/Perseverance) that uses retrorocket engines to slow the spacecraft for a soft touchdown, rather than relying solely on parachutes or airbags.

Crew Autonomy

Human Exploration & Life Support
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Crew Autonomy

The level of independence a Mars crew must have. Due to the ~40-minute round-trip communication delay, the crew cannot rely on Mission Control on Earth for emergencies or daily decisions, requiring a high degree of autonomy.

Martian Gullies

Planetary Science & Geology
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Martian Gullies

Small channels and debris aprons found on the slopes of craters and valleys, primarily in the mid-latitudes. Their young appearance suggested they might be formed by liquid water flows, though seasonal CO2 is now thought to play a key role.

Beagle 2

Missions & Programs
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Beagle 2

A British lander (part of the ESA Mars Express mission) launched in 2003. Its objective was to search for signs of life. The mission failed after separating from the orbiter, and contact was lost. Years later, MRO located it on the surface, indicating it had partially deployed.

Biosignature

Planetary Science & Geology
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Biosignature

Any substance, object, or pattern whose presence unequivocally indicates the existence of life, either past or present. It can be a fossil, a complex organic molecule, or a specific isotopic pattern.

Robotic Arm (Exploration)

Technology & Instruments
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Robotic Arm (Exploration)

An articulated device (like on rovers and landers) that serves as the main scientist's "arm". It is used to deploy contact instruments (like PIXL, SHERLOC, or the RAT) and to collect samples (drilling or scooping).

Vacuum Chamber (Space)

Technology & Instruments
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Vacuum Chamber (Space)

A test facility on Earth that simulates the vacuum of space or the thin atmosphere of Mars. It is used to subject spacecraft, instruments, and suits to low-pressure and extreme temperature conditions (thermal-vacuum) before launch.

Candor Chasma

Planetary Science & Geology
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Candor Chasma

One of the largest and most northern canyons in the Valles Marineris system. It is noted for its complex internal sedimentary deposits (layers) that suggest a history of water or wind deposition.

Carbonates

Planetary Science & Geology
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Carbonates

Minerals (like calcite) that form from the precipitation of CO2 and cations (like calcium) in water. Their relative scarcity on the Martian surface is a puzzle, though the Spirit rover and Perseverance (in Jezero) have found deposits, suggesting more neutral water environments.

Polar Ice Caps (Planum Boreum / Planum Australe)

Planetary Science & Geology
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Polar Ice Caps (Planum Boreum / Planum Australe)

The polar regions of Mars. They consist of a permanent cap of water ice (which survives summer) overlaid by a seasonal cap of carbon dioxide ice (dry ice) that expands and sublimes each year.

Planetary Protection Category IV

Missions & Programs
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Planetary Protection Category IV

The strictest planetary protection classification (defined by COSPAR). It applies to missions (like astrobiology rovers) that land on Mars and search for life. It requires rigorous sterilization to avoid contaminating Mars with Earth microbes ("forward contamination").

Planetary Protection Category V

Missions & Programs
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Planetary Protection Category V

A classification that applies to Sample Return missions. It imposes strict requirements for the return ("backward contamination"), requiring that Martian samples be hermetically contained and treated as hazardous until proven otherwise, to protect Earth's biosphere.

ChemCam

Technology & Instruments
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ChemCam

An instrument on the Curiosity rover's mast. It uses a laser (LIBS - Laser-Induced Breakdown Spectroscopy) to vaporize a small spot on a rock from a distance and a spectrometer to analyze the chemical composition of the resulting plasma.

Chryse Planitia

Missions & Programs
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Chryse Planitia

A vast circular plain in the northern hemisphere. It is the outflow point for several large outflow channels (like Ares Vallis). It was the landing site for Viking 1 (1976) and Mars Pathfinder (1997).

Milankovitch Cycles (Martian)

Planetary Science & Geology
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Milankovitch Cycles (Martian)

Long-term climate changes caused by cyclical variations in Mars's orbit (eccentricity) and its axial tilt (obliquity). On Mars, these cycles are far more extreme than on Earth and have caused drastic ice ages and interglacials.

Freeze-Dried Food

Human Exploration & Life Support
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Freeze-Dried Food

The primary food preservation method for long-duration missions. Food is cooked, rapidly frozen, and then placed in a vacuum to sublimate the ice. The result is a very lightweight, shelf-stable food that is rehydrated on the spacecraft.

Solar Conjunction

Technology & Instruments
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Solar Conjunction

A period when Mars and Earth are on opposite sides of the Sun. During this time, solar plasma interferes with and corrupts radio communications, forcing space agencies to suspend sending commands to missions at Mars (a "command moratorium") for safety.

Countermeasures (Physiological)

Human Exploration & Life Support
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Countermeasures (Physiological)

The exercises, diets, and devices (like ARED on the ISS) designed to mitigate the negative effects of microgravity on the human body (bone loss, muscle atrophy). Developing effective countermeasures for the ~9-month trip to Mars is a critical challenge.

Mission Control (MCC)

Technology & Instruments
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Mission Control (MCC)

The operations center on Earth (like at JPL or ESOC) that manages the spacecraft. Teams at the MCC plan command sequences, analyze telemetry (health data), and receive the scientific data from the missions.

COSPAR

Missions & Programs
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COSPAR

Acronym for the "Committee on Space Research". An international scientific organization that, among other things, develops and maintains Planetary Protection policy, providing guidelines that space agencies (NASA, ESA) voluntarily follow.

Airy Crater

Planetary Science & Geology
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Airy Crater

A 43 km impact crater in the Sinus Meridiani region. Its importance is geographical: A smaller crater *inside* it (Airy-0) was chosen to define the Prime Meridian (0° longitude) for Mars.

Bonneville Crater

Missions & Programs
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Bonneville Crater

A 210-meter crater in Gusev Crater, visited by the Spirit rover. Spirit drove to its rim, but it was determined not to offer compelling enough geological targets to warrant a risky entry.

Eagle Crater

Missions & Programs
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Eagle Crater

A small (22-meter) impact crater in Meridiani Planum. It is the landing site of the Opportunity rover (MER-B). Though tiny, its importance is immense, as it was here that Opportunity found the rock outcrop with the first evidence of liquid surface water.

Eberswalde Crater

Missions & Programs
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Eberswalde Crater

A crater in the southern highlands containing one of the best-preserved fossil river deltas on Mars. It was a primary finalist for the landing site of the MSL (Curiosity) mission.

Endeavour Crater

Missions & Programs
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Endeavour Crater

The final and longest-term exploration site for the Opportunity rover (22 km diameter). Its rim exposed rocks far older than the surrounding plains, including evidence of clay minerals (phyllosilicates) that indicated a past with neutral-pH water.

Endurance Crater

Missions & Programs
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Endurance Crater

A 130-meter crater explored by the Opportunity rover. It was the first "large" crater the rover entered, allowing it to analyze a much deeper cross-section of rock layers than seen at Eagle Crater.

Gale Crater

Missions & Programs
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Gale Crater

A 154 km crater hosting "Mount Sharp" (Aeolis Mons). It is the landing site for the Curiosity rover (MSL). It was chosen for its central mound of layered sediments that act as a record of Mars's geological and climate history.

Gusev Crater

Planetary Science & Geology
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Gusev Crater

A 166 km diameter impact crater that was the landing site for the Spirit rover (MER-A). It was chosen because a channel (Ma'adim Vallis) appeared to have once filled it with water, forming a lake, though the initial findings were volcanic.

Heaviside Crater

Planetary Science & Geology
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Heaviside Crater

A large, 87 km crater in southern Mars, notable for having a field of dark, bluish dunes (composed of basalt) on its floor, which contrasts sharply with the surrounding lighter terrain.

Holden Crater

Missions & Programs
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Holden Crater

A large crater (154 km) that was also a finalist for the MSL and ExoMars missions. It contains lake sediment (lacustrine) deposits and evidence of multiple episodes of water flows.

Huygens Crater

Planetary Science & Geology
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Huygens Crater

One of the largest and oldest impact craters (467 km) in the Martian highlands. It is notable because its rim shows evidence of carbonate minerals, suggesting a non-acidic water history.

Jezero Crater

Planetary Science & Geology
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Jezero Crater

The landing site for the Perseverance rover. It is an ancient impact crater that, billions of years ago, hosted a lake and a prominent river delta. It is an ideal site to search for biosignatures preserved in the sediments.

Korolev Crater

Planetary Science & Geology
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Korolev Crater

An 82 km crater in the northern polar plains (Planum Boreum). It is famous for containing a massive, permanent deposit of water ice (not dry ice) 1.8 km thick, which is preserved by a "cold trap" phenomenon.

Lomonosov Crater

Planetary Science & Geology
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Lomonosov Crater

A 150 km crater in the arctic plains. It has gained interest because its shape and surrounding deposits are consistent with the theory of a "megatsunami" caused by an impact into an ancient Martian ocean (Borealis Ocean).

Lyot Crater

Planetary Science & Geology
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Lyot Crater

A large impact crater (236 km) in the northern lowlands. It is the deepest point in the northern hemisphere and is considered a "young" crater by Martian standards. It displays glacial/liquid water flow features.

McLaughlin Crater

Planetary Science & Geology
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McLaughlin Crater

A large and very deep impact crater (92 km wide, 2.2 km deep). Its depth is such that it is thought to have interacted with the water table, showing evidence of minerals (clays, carbonates) that formed in a groundwater-fed lake.

Santa Maria Crater

Missions & Programs
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Santa Maria Crater

A relatively "young" crater (90 meters) visited by the Opportunity rover. The rover studied its rim and sulfate deposits, providing more data on the history of water in Meridiani Planum before continuing its journey to Endeavour.

Schiaparelli Crater

Missions & Programs
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Schiaparelli Crater

A large impact basin (460 km) near the equator. It is famous for being the intended landing site for the Schiaparelli EDM lander (of the ExoMars 2016 mission), which crashed during its landing sequence.

Victoria Crater

Missions & Programs
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Victoria Crater

A large impact crater (750 meters) explored by the Opportunity rover. The rover spent nearly two years circumnavigating and exploring its rim and layered cliffs (Cape St. Vincent), which revealed a complex geological history.

CRISM

Technology & Instruments
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CRISM

Acronym for "Compact Reconnaissance Imaging Spectrometer for Mars". A key spectrometer on MRO that maps the surface mineralogical composition. It has been fundamental in identifying phyllosilicates and sulfates, tracing the history of water.

Curiosity (Rover)

Missions & Programs
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Curiosity (Rover)

NASA's rover (Mars Science Laboratory mission, MSL) that landed in Gale Crater in 2012. Its primary objective is to assess Mars' past and present habitability. It discovered conclusive evidence of an ancient freshwater lake.

Deimos

Planetary Science & Geology
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Deimos

The smaller and more distant of Mars's two moons. Like Phobos, it is a small, irregular body with a heavily cratered surface, believed to be an asteroid captured by Mars's gravity.

Delta (Fluvial Geology)

Planetary Science & Geology
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Delta (Fluvial Geology)

A fan-shaped geological formation created by the deposition of sediment carried by a river as it enters a larger body of water (like a lake). The Jezero Crater delta is the primary target of study for Perseverance.

Delta-v

Technology & Instruments
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Delta-v

An orbital mechanics term meaning "change in velocity". It is the measure of the propulsion "effort" required to perform a maneuver, such as a launch, an orbital insertion, or an interplanetary transfer.

Sample Depot

Missions & Programs
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Sample Depot

A strategically chosen location on the Martian surface (like "Three Forks" in Jezero) where the Perseverance rover drops a duplicate set of sealed sample tubes. It serves as a backup for the Sample Return mission in case the rover fails.

Spatial Disorientation

Human Exploration & Life Support
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Spatial Disorientation

An astronaut's inability to correctly determine their body orientation or the direction of "up" and "down," caused by the lack of gravity. It is a significant risk during the transition from microgravity (transit) to Martian gravity (1/3g).

Dust Devil

Planetary Science & Geology
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Dust Devil

A small, rotating, and ascending wind vortex, similar to a tornado, made visible by lifting surface dust. They are very common on Mars and have been photographed (and have even cleaned the solar panels of the MER rovers).

Crustal Dichotomy

Planetary Science & Geology
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Crustal Dichotomy

One of Mars's most prominent geographic features. It is the extreme topographic difference between the low, smooth plains of the northern hemisphere and the ancient, heavily cratered highlands of the southern hemisphere. Its origin (giant impact or tectonics) is still debated.

Equivalent Dose (Radiation)

Human Exploration & Life Support
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Equivalent Dose (Radiation)

A measure of the biological damage caused by radiation, weighted by the radiation type (GCRs are more damaging than X-rays). It is measured in Sieverts (Sv). Protecting the crew from exceeding career dose limits is a primary driver of human exploration.

Dunes (Martian)

Planetary Science & Geology
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Dunes (Martian)

Accumulations of sand (composed mainly of dark basalt) moved by the wind. Many dune types (barchan, transverse, longitudinal) are observed on Mars, indicating current wind patterns.

Earth Return Orbiter (ERO)

Missions & Programs
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Earth Return Orbiter (ERO)

The ESA component of the Mars Sample Return (MSR) campaign. It will be a spacecraft that orbits Mars, rendezvous with the MAV to capture the samples, and then use Solar Electric Propulsion (SEP) to fly the sample container back to Earth.

ECLSS

Human Exploration & Life Support
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ECLSS

Acronym for "Environmental Control and Life Support System". A set of regenerative technologies that provide clean air (recycling CO2), potable water (recycling greywater and urine), and temperature control in a crewed habitat.

Ecopoiesis

Human Exploration & Life Support
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Ecopoiesis

A term (related to terraforming) describing the process of introducing life (usually microbial or plant life) into a sterile environment to initiate the creation of a self-sustaining biosphere. It would be a precursor step to full terraforming.

EDL (Entry, Descent, and Landing)

Technology & Instruments
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EDL (Entry, Descent, and Landing)

The most critical and complex phase of a robotic mission to Mars, where the spacecraft must decelerate from hypersonic speeds to a safe landing on the surface. Due to Mars' thin atmosphere, this sequence is notoriously difficult and often called the "seven minutes of terror".

Microgravity Effects

Human Exploration & Life Support
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Microgravity Effects

The adverse physiological effects of long-duration space travel, including bone density loss (osteopenia), muscle atrophy, and changes to the cardiovascular system. They are a key challenge for crew health on the journey to and from Mars.

Water Electrolysis

Human Exploration & Life Support
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Water Electrolysis

The process of using electricity (from solar panels or an RTG) to split water (H2O) into its components: hydrogen (H2) and oxygen (O2). It is crucial for ISRU, producing breathable oxygen and H2 for the Sabatier reaction.

Elysium Planitia

Missions & Programs
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Elysium Planitia

The second major volcanic province on Mars (after Tharsis). It is a lava plain with several volcanoes, including Elysium Mons. It is the landing site for the InSight geophysical mission.

Mass Spectrometry

Technology & Instruments
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Mass Spectrometry

A fundamental analytical technique (used in SAM and Viking). It works by ionizing a sample (gas) and separating the ions by their mass-to-charge ratio. It is extremely precise for identifying which molecules (including organics) are present in the atmosphere or soil.

Spectrometer

Technology & Instruments
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Spectrometer

A scientific instrument that measures the properties of light (the electromagnetic spectrum) interacting with a material. It is used to determine the chemical and mineralogical composition of rocks, soil, and the atmosphere.

Raman Spectroscopy

Technology & Instruments
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Raman Spectroscopy

An analytical technique (used by SHERLOC and SuperCam). It illuminates a target with a single-wavelength laser. The way the light scatters reveals the material's molecular structure, allowing non-destructive identification of minerals and organic compounds.

Gateway Station

Human Exploration & Life Support
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Gateway Station

A future space station in lunar orbit (Artemis Program). It is designed to serve as a staging ground, laboratory, and staging post for crewed missions, both to the lunar surface and, eventually, to Mars (Deep Space Transport).

Solar Particle Event (SPE)

Planetary Science & Geology
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Solar Particle Event (SPE)

An emission of high-energy particles (primarily protons) by the Sun, often associated with solar flares. During transit to Mars, an SPE poses an acute radiation risk to the crew if they do not have a shielded "storm shelter".

Orbital Eccentricity

Planetary Science & Geology
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Orbital Eccentricity

A measure of how much an orbit deviates from a perfect circle. Mars has a high orbital eccentricity, meaning its distance from the Sun varies greatly. This causes seasons of unequal length and significantly affects its climate.

ExoMars

Missions & Programs
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ExoMars

A Mars exploration program by the European Space Agency (ESA), in (originally) collaboration with Roscosmos. It includes the Trace Gas Orbiter (TGO), currently orbiting Mars to study trace gases like methane.

Phyllosilicates (Clays)

Planetary Science & Geology
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Phyllosilicates (Clays)

A group of minerals (like montmorillonite) that form from the alteration of rock in the presence of liquid water, usually of neutral pH. Their presence in Noachian-aged rocks suggests habitable conditions on early Mars.

Phobos

Planetary Science & Geology
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Phobos

The larger and closer of Mars's two moons. It is an irregular, dark object, likely a captured asteroid or impact debris. It is a target for future missions, such as Japan's "Martian Moons eXploration" (MMX).

Medusae Fossae Formation

Planetary Science & Geology
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Medusae Fossae Formation

A vast geological unit at the Mars equator, composed of soft, easily wind-eroded sedimentary rock (creating yardangs). Its origin is a mystery; it could be an immense deposit of volcanic ash (ignimbrite) or dust.

Rock Glaciers

Planetary Science & Geology
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Rock Glaciers

Common geological formations in Mars's mid-latitudes. They are glacier-like flows composed of a mix of rocks, debris, and a high amount of interstitial water ice, indicating a recent past with widespread ice.

Goethite

Planetary Science & Geology
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Goethite

An iron oxy-hydroxide mineral. Its identification on Mars (by the Spirit rover in Gusev Crater) was conclusive proof of significant aqueous alteration, as goethite forms in the presence of water.

Sky Crane

Technology & Instruments
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Sky Crane

The innovative landing system (EDL) developed by NASA for the Curiosity and Perseverance rovers. It is a rocket-powered descent stage that lowers the rover on cables to the surface, releases it, and then flies away to crash at a safe distance.

Surface Habitat

Human Exploration & Life Support
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Surface Habitat

The pressurized, radiation-shielded structure where astronauts will live and work on the Martian surface. It must be robotically deployed or constructed in-situ, possibly using Martian regolith.

Hellas Planitia

Planetary Science & Geology
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Hellas Planitia

A giant impact basin (not just a crater) in the southern hemisphere. It is the lowest elevation point on Mars, with a depth of over 7 km. Because of this, the atmospheric pressure at its bottom is significantly higher than the Martian average.

Hematite (Spherules)

Planetary Science & Geology
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Hematite (Spherules)

An iron oxide (Fe2O3). The Opportunity rover found hematite in the form of small spherules ("blueberries"). On Earth, these concretions often form from precipitation in groundwater, reinforcing the evidence of liquid water.

Rock Abrasion Tool (RAT)

Technology & Instruments
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Rock Abrasion Tool (RAT)

An instrument used by the Spirit and Opportunity rovers. It was a small grinding tool located on the robotic arm, designed to wear away the weathered outer layer of rocks to expose the pristine interior for analysis.

Hesperia Planum

Planetary Science & Geology
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Hesperia Planum

An elevated lava plain in the southern hemisphere. It is the type locality for the Hesperian Period (the second geological period of Mars), characterized by intense volcanism and lava plain formation.

Hydroponics

Human Exploration & Life Support
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Hydroponics

A method of growing plants without soil, using mineral nutrient solutions in an aqueous solvent. It is a key technology being tested for fresh food production on long-duration space missions.

Hypercapnia

Human Exploration & Life Support
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Hypercapnia

A medical condition caused by an excess of carbon dioxide (CO2) in the bloodstream. It is a constant risk in enclosed environments like spacecraft or habitats, requiring reliable ECLSS systems to "scrub" CO2 from the crew's breathing air.

HiRISE

Technology & Instruments
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HiRISE

Acronym for "High Resolution Imaging Science Experiment". The most powerful telescopic camera in Martian orbit, onboard the MRO. It can image the surface with sub-meter resolution, allowing it to see rovers and fine geological details.

HP3 (Heat Probe)

Technology & Instruments
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HP3 (Heat Probe)

An instrument on the InSight mission (Heat Flow and Physical Properties Package), designed to burrow 5 meters beneath the surface to measure the heat flow escaping from Mars's interior.

Ignimbrite

Planetary Science & Geology
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Ignimbrite

A volcanic rock formed from the deposit of hot pyroclastic flows (ash, pumice, and gas). It is one of the leading theories to explain the origin of the Medusae Fossae Formation on Mars.

3D Printing (Additive Manufacturing)

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3D Printing (Additive Manufacturing)

A key technology for human exploration. It will allow crews to manufacture tools, spare parts, or even habitats (using Martian regolith) in-situ, drastically reducing the cargo mass that must be launched from Earth.

Specific Impulse (Isp)

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Specific Impulse (Isp)

A measure of rocket engine efficiency. It measures how much "impulse" (change in momentum) is obtained per unit of propellant consumed. A higher Isp means the engine is more efficient and can achieve more "delta-v" with less fuel.

Axial Tilt (Obliquity)

Planetary Science & Geology
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Axial Tilt (Obliquity)

The tilt of a planet's axis of rotation relative to its orbital plane. Mars's tilt (25.2°) is very similar to Earth's (23.5°), which gives Mars distinct seasons. However, its obliquity has varied wildly in the past.

Ingenuity (Helicopter)

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Ingenuity (Helicopter)

An experimental robotic helicopter that accompanied the Perseverance rover. It successfully demonstrated the viability of powered, controlled flight in the extremely thin Martian atmosphere, serving as an aerial scout.

Human-Machine Interface (HMI)

Human Exploration & Life Support
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Human-Machine Interface (HMI)

The systems (displays, controls, software) that allow astronauts to operate and monitor complex systems like the spacecraft, rovers, or habitat. Given the communication delay, HMI on Mars must be intuitive and allow for full autonomy.

Isidis Planitia

Planetary Science & Geology
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Isidis Planitia

A massive impact basin located at the boundary of the crustal dichotomy. The Perseverance rover landed on its western rim (at Jezero Crater). It is one of the oldest impact basins on Mars.

ISRU (In-Situ Resource Utilization)

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ISRU (In-Situ Resource Utilization)

A space engineering concept involving the collection, processing, and use of materials found or manufactured on the celestial body itself (like Mars) to reduce dependency on supplies from Earth. Example: Producing oxygen or propellant from the Martian atmosphere (like the MOXIE experiment).

Ius Chasma

Planetary Science & Geology
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Ius Chasma

One of the main (southern) canyons that make up the Valles Marineris system. It is known for its "Linear Erosion Valleys" (LEVs) and sulfate deposits.

Jarosite

Planetary Science & Geology
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Jarosite

A potassium iron sulfate mineral. Its discovery by the Opportunity rover was crucial, as this mineral only forms on Earth in highly acidic aqueous environments, indicating the type of water that existed at Meridiani Planum.

Kasei Valles

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Kasei Valles

One of the largest outflow channel systems on Mars, stretching over 3,000 km. It was carved by massive floods (possibly originating from Tharsis volcanism) that flowed towards Chryse Planitia.

Medical Kit (Exploration)

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Medical Kit (Exploration)

The set of medical supplies and diagnostic equipment a crewed mission must carry. It must be ablef to handle a wide range of emergencies (from fractures to surgery) autonomously, without real-time support from Earth.

Subglacial Lakes (Mars)

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Subglacial Lakes (Mars)

Bodies of liquid water theorized to exist beneath the Martian south polar ice cap. They were detected by the MARSIS radar (on Mars Express) as bright reflections. It is believed high pressure from the ice and the presence of salts (perchlorates) keep the water liquid.

LIBS (Laser-Induced Breakdown Spectroscopy)

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LIBS (Laser-Induced Breakdown Spectroscopy)

The analytical technique used by the ChemCam and SuperCam instruments. It involves firing a high-power laser at a rock, creating a plasma (superheated gas) that emits light. Analyzing the spectrum of that light reveals the rock's elemental composition.

LIDAR

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LIDAR

Acronym for "Light Detection and Ranging". A remote sensing technology that uses laser pulses to measure distances and create high-precision 3D maps of the terrain. It is crucial for autonomous navigation and precision landing (TRN assist).

Recurring Slope Lineae (RSL)

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Recurring Slope Lineae (RSL)

Dark, narrow markings that appear and grow seasonally on warm Martian slopes. They were initially theorized as flowing brine, though the currently accepted hypothesis suggests dry sand or dust flows.

Ma'adim Vallis

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Ma'adim Vallis

A large, ancient canyon (longer than the Grand Canyon) thought to be carved by liquid water. It is notable because it drains into Gusev Crater, which is why Gusev was chosen as the landing site for the Spirit rover.

Magnetometer

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Magnetometer

A scientific instrument designed to measure the strength and direction of magnetic fields. Magnetometers on orbiters (like Mars Global Surveyor and MAVEN) were what discovered the crustal magnetic anomalies and measured how the solar wind interacts with the atmosphere.

Magnetosphere

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Magnetosphere

A region around a planet dominated by its magnetic field. Mars, unlike Earth, does not have a global magnetic field (it lost it billions of years ago), but rather local "magnetic anomalies" in the crust. This lack of a shield is why the solar wind has stripped its atmosphere.

Mantle (Planetary)

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Mantle (Planetary)

The internal layer of a planet situated between the crust and the core. The Martian mantle is believed to be solid (unlike Earth's partially molten mantle) and composed primarily of silicates.

Mars 3

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Mars 3

A Soviet Union mission (1971) that included an orbiter and a lander. It achieved the first successful soft landing on the Martian surface, but the lander failed and stopped transmitting data just 14.5 seconds after landing, likely due to a global dust storm.

Mars 96

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Mars 96

An ambitious Russian space mission (1996) consisting of an orbiter, two surface stations, and two penetrators. It failed catastrophically when its Proton rocket's upper stage failed, and the spacecraft re-entered Earth's atmosphere.

Mars Direct

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Mars Direct

An influential human mission architecture for Mars, proposed by Robert Zubrin. Its philosophy is "travel light" and "live off the land" (ISRU). It proposes sending an uncrewed Earth Return Vehicle (ERV) first, which manufactures its own methane fuel on Mars before the crew ever launches.

Mars Exploration Rovers (MER)

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Mars Exploration Rovers (MER)

The 2003 NASA mission that included the two twin rovers: Spirit (MER-A) and Opportunity (MER-B). Their primary objective was to "follow the water," and both found conclusive evidence of liquid water in the Martian past.

Mars Express (MEX)

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Mars Express (MEX)

The European Space Agency's (ESA) first interplanetary mission, launched in 2003. It has been operating for two decades, mapping the surface, studying the atmosphere, and using its MARSIS radar to find evidence of subsurface water.

Mars Global Surveyor (MGS)

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Mars Global Surveyor (MGS)

A NASA orbital mission (1996-2006) that mapped Mars in high resolution. Its instruments (like MOLA and MOC) provided the first detailed 3D topographic map, discovered gullies, and identified hematite fields, guiding future missions.

Mars Odyssey (ODY)

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Mars Odyssey (ODY)

A NASA orbiter launched in 2001, it is the longest-serving spacecraft at Mars. It is famous for its Gamma Ray Spectrometer (GRS), which detected the presence of vast quantities of water ice just beneath the surface of the polar regions.

Mars Orbiter Mission (MOM)

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Mars Orbiter Mission (MOM)

India's first interplanetary mission (ISRO), launched in 2013. Known as "Mangalyaan," it was a technology demonstration mission that successfully entered Mars orbit, making India the fourth agency to achieve this.

Mars Pathfinder (Sojourner)

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Mars Pathfinder (Sojourner)

A NASA mission (1997) that demonstrated a low-cost way to land (using airbags) and deploy the first-ever rover on Mars, "Sojourner". It was a technology demonstration mission that captured the public's imagination.

Mars Polar Lander (MPL)

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Mars Polar Lander (MPL)

A 1999 NASA mission that failed during landing. The craft (which also carried the Deep Space 2 probes) was intended to land near the south pole to study climate and ice, but contact was lost. The failure was attributed to a premature shutdown of the descent engine.

Mars Reconnaissance Orbiter (MRO)

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Mars Reconnaissance Orbiter (MRO)

A NASA multipurpose orbiter (launched in 2005) that has revolutionized our understanding of Mars. Its mission is to search for evidence of past water, study the climate and geology, and identify landing sites for future missions.

Marsquake

Planetary Science & Geology
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Marsquake

A seismic event on Mars, analogous to an earthquake on Earth. Marsquakes detected by InSight are key to mapping the planet's internal structure.

MAVEN

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MAVEN

Acronym for "Mars Atmosphere and Volatile Evolution". A NASA orbital mission (launched 2013) dedicated to studying Mars's upper atmosphere. Its objective is to understand how Mars lost most of its atmosphere and liquid water, primarily stripped away by the solar wind.

Mawrth Vallis

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Mawrth Vallis

An ancient outflow channel that is one of the highest astrobiology targets on Mars. It exposes layered rocks rich in phyllosilicates (clays) that preserve a record of neutral-pH aqueous conditions on early Mars. It was a finalist for Curiosity and ExoMars.

MEDA (Mars Environmental Dynamics Analyzer)

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MEDA (Mars Environmental Dynamics Analyzer)

The weather station aboard the Perseverance rover. It is a suite of sensors that measures temperature, wind speed and direction, pressure, humidity, and the properties of dust in the Martian atmosphere.

Melas Chasma

Planetary Science & Geology
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Melas Chasma

The widest and deepest canyon of Valles Marineris. Its floor lies about 9 km below the surrounding plateau. It contains a vast dune field and sulfate deposits, indicating a past aqueous environment.

Meridiani Planum

Planetary Science & Geology
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Meridiani Planum

A plain on Mars chosen as the landing site for the Opportunity rover (MER-B) because of its high concentration of the mineral hematite (detected from orbit), which often forms in the presence of water.

Methane (on Mars)

Planetary Science & Geology
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Methane (on Mars)

A trace gas in the Martian atmosphere whose detection is scientifically significant. Methane is photochemically unstable (destroyed by sunlight), so its presence, though sporadic, implies an active replenishment source, which could be geological (serpentinization) or, hypothetically, biological.

Martian Meteorite (SNC)

Planetary Science & Geology
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Martian Meteorite (SNC)

A meteorite found on Earth whose chemical composition (trapped gases) matches the atmosphere of Mars, proving it was ejected from Mars by a large impact. These (Shergottites, Nakhlites, Chassignites - SNC) were the only way to study Martian rocks before rovers.

Conjunction-Class Mission

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Conjunction-Class Mission

A human mission architecture that optimizes for energy efficiency (using Hohmann transfers). It involves a 6-9 month transit, a *long* stay on Mars (e.g., ~500 days) waiting for the next return window, and a 6-9 month transit back. This is the "Mars Direct" architecture.

Opposition-Class Mission

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Opposition-Class Mission

A human mission architecture that prioritizes short *total* mission time. It involves a fast transit to Mars, a short stay on the surface (e.g., 30-90 days), and a fast transit back. It is very energy-intensive and does not align with minimum-energy launch windows.

Sample Return Mission

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Sample Return Mission

A robotic space mission designed to collect samples from a celestial body (like Mars) and return them to Earth for detailed analysis in advanced laboratories.

Hope Mission (Emirates Mars Mission)

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Hope Mission (Emirates Mars Mission)

The first interplanetary mission by the United Arab Emirates (launched 2020). It is an orbiter designed to study Mars's climate and atmosphere throughout a full Martian year, providing the first global picture of atmospheric dynamics.

InSight Mission

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InSight Mission

A NASA mission (launched 2018) designed to study the deep interior of Mars. Its objective was to investigate the planet's internal structure (crust, mantle, and core) and tectonic activity using a seismometer.

Phobos Mission

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Phobos Mission

Two space probes (Phobos 1 and 2) launched by the Soviet Union in 1988 to study Mars and its moons. Phobos 1 failed en route. Phobos 2 orbited Mars and returned data, but contact was lost just before it was to deploy its landers on the moon Phobos.

MMX (Martian Moons eXploration)

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MMX (Martian Moons eXploration)

An upcoming mission by the Japanese space agency (JAXA) aimed at exploring the moons Phobos and Deimos. The mission plans to land on Phobos and collect a surface sample to return to Earth.

MOC (Mars Orbiter Camera)

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MOC (Mars Orbiter Camera)

Instrument (camera) aboard the Mars Global Surveyor. It provided medium and high-resolution images that were fundamental for mapping and discovering features like gullies, suggesting recent water flows.

Phoenix Lander

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Phoenix Lander

A NASA mission (2008) that landed in the Martian arctic region (Vastitas Borealis). Its objective was to study subsurface water ice. It was the first mission to directly touch and analyze Martian water ice.

MOLA (Laser Altimeter)

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MOLA (Laser Altimeter)

Acronym for "Mars Orbiter Laser Altimeter". Instrument aboard the Mars Global Surveyor. It fired laser pulses at the surface to create an incredibly precise 3D topographic map of Mars, revealing the crustal dichotomy and measuring volcano heights.

Grinder (Robotic Arm)

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Grinder (Robotic Arm)

A general term for an abrasion tool (like the RAT or the one on Perseverance) that removes dust and surface patina from a rock before instruments like PIXL or SHERLOC analyze it.

Olympus Mons

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Olympus Mons

A massive shield volcano and the tallest known volcano in the Solar System. Its enormous size (nearly 22 km high) is likely the result of Mars' low gravity and the lack of mobile tectonic plates.

MOXIE

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MOXIE

Acronym for "Mars Oxygen In-Situ Resource Utilization Experiment". An instrument aboard the Perseverance rover that demonstrated the ability to produce molecular oxygen (O2) directly from the carbon dioxide (CO2) in the Martian atmosphere.

Terrain-Relative Navigation (TRN)

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Terrain-Relative Navigation (TRN)

An advanced landing system (used by Perseverance) that allows the spacecraft to compare real-time images from its descent camera with a high-resolution orbital map. This enables it to identify its exact location and divert from hazards (rocks, dunes) to land at a safe site.

Nili Fossae

Planetary Science & Geology
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Nili Fossae

A system of tectonic troughs (grabens) on the rim of the Isidis impact basin. It is of high astrobiological interest, as orbital observations have revealed a rich diversity of water-altered minerals, including carbonates and clays.

Nirgal Vallis

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Nirgal Vallis

One of the longest valley systems on Mars, resembling a terrestrial tributary network. It is believed to have formed by groundwater "sapping" (erosion) rather than by rainfall.

Noctis Labyrinthus

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Noctis Labyrinthus

The "Labyrinth of the Night". A complex, deeply intersecting system of valleys, canyons, and tectonic troughs (grabens). It sits at the western end of Valles Marineris and is associated with Tharsis volcanism.

Carbon Dioxide Clouds

Planetary Science & Geology
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Carbon Dioxide Clouds

Clouds composed of dry ice (solid CO2) that form in the Martian atmosphere, especially in the polar regions during winter when temperatures drop below -125°C.

Water Ice Clouds

Planetary Science & Geology
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Water Ice Clouds

Thin, high-altitude clouds in the Martian atmosphere composed of water ice crystals (similar to Earth's cirrus clouds). They often form over the peaks of volcanoes (orographic clouds).

Core (Planetary)

Planetary Science & Geology
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Core (Planetary)

The innermost center of a planet. Thanks to the InSight mission, it was confirmed that Mars has a large, liquid (or at least partially liquid) core, composed mainly of iron and nickel, with a surprising amount of light elements like sulfur.

Olivine

Planetary Science & Geology
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Olivine

A common silicate mineral in Mars's basaltic rocks. Its importance lies in its rapid alteration (weathering) in the presence of liquid water. The discovery of large olivine deposits indicates areas that have been extremely dry for billions of years.

Ophir Chasma

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Ophir Chasma

A tributary (northern) canyon of the Valles Marineris system, connected to Candor Chasma. It is notable for its steep walls and evidence of massive landslides.

Mars Opposition

Planetary Science & Geology
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Mars Opposition

Orbital configuration occurring approximately every 26 months, where Earth passes directly between the Sun and Mars. At this point, Mars is at its closest approach to Earth, making it appear brighter and defining the center of the "launch window".

Opportunity (MER-B)

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Opportunity (MER-B)

The twin rover of Spirit (MER) that landed in Meridiani Planum. Famous for its longevity (operated 2004-2018). It discovered the hematite "blueberries" and the mineral jarosite, irrefutable evidence of a past with acidic and saline water.

Areocentric Orbit

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Areocentric Orbit

The technical term for any orbit around the planet Mars. (Derived from "Ares", the Greek god of war, equivalent to the Roman Mars).

Areosynchronous Orbit

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Areosynchronous Orbit

An areocentric orbit (around Mars) whose orbital period matches Mars's sidereal day (24.62 hours). It is the Martian analogue of a Earth's geosynchronous orbit.

Hohmann Transfer Orbit

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Hohmann Transfer Orbit

An energy-efficient orbital maneuver used to transfer a spacecraft between two circular, coplanar orbits. It is the standard, lowest-energy consumption method for traveling from Earth to Mars.

Paleoclimatology

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Paleoclimatology

The study of past climates. On Mars, this involves analyzing geology (rock layers, minerals) and polar ice deposits to understand how the planet's climate evolved from warm and wet to the current frozen desert.

Supersonic Parachute

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Supersonic Parachute

A parachute designed to deploy and operate at speeds greater than the speed of sound (Mach 1). It is a critical component of the EDL sequence in Mars's thin atmosphere to slow the spacecraft (like Perseverance) before retrorockets fire.

Pavonis Mons

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Pavonis Mons

The central volcano of the three "Tharsis Montes" (along with Arsia and Ascraeus). It is a massive shield volcano located exactly on the Martian equator.

Perchlorate

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Perchlorate

A type of salt (an anion containing chlorine and oxygen) that has been detected in abundance in Martian soil. Its presence has significant implications for both habitability (it is a potential energy source for microbes) and human exploration (it is toxic to humans).

Periapsis (Periareion)

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Periapsis (Periareion)

The point in an elliptical orbit around a body (Mars) where the spacecraft is closest to the planet. It is the point of maximum orbital velocity. (The Mars-specific term is Periareion).

Amazonian Period

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Amazonian Period

The most recent geological period of Mars (from 3.0 billion years ago to the present). It is a cold, dry period dominated by wind erosion, ice formation, and very low geological activity. It is the "modern" Mars.

Hesperian Period

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Hesperian Period

The second geological period of Mars (approx. 3.7 to 3.0 billion years ago). It is characterized by intense volcanic activity and the formation of vast lava plains. Liquid water became more sporadic and likely acidic and saline.

Noachian Period

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Noachian Period

The earliest geological era of Mars (approx. 4.1 to 3.7 billion years ago). It is characterized by high asteroid impact rates and widespread evidence of surface liquid water, making it the period of highest astrobiological interest.

Perseverance (Rover)

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Perseverance (Rover)

NASA's rover (Mars 2020 Mission) that landed in Jezero Crater. Its main objectives are to seek signs of ancient microbial life (biosignatures), collect and cache rock samples for future return to Earth, and test new technologies.

Pyroxene

Planetary Science & Geology
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Pyroxene

A group of silicate minerals that are fundamental components of basalt, the most common volcanic rock on Mars. Pyroxene composition (high vs. low calcium) helps geologists understand magma evolution and the history of the Martian crust.

PIXL

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PIXL

Acronym for "Planetary Instrument for X-ray Lithochemistry". An instrument on Perseverance's robotic arm that uses a high-precision X-ray beam to map the elemental composition of rocks at a sub-millimeter scale.

Martian Dust

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Martian Dust

Fine particles (perchlorated and electrostatic) that cover much of the surface. It poses a significant engineering challenge, as it can cling to spacesuits, infiltrate mechanisms, and reduce the efficiency of solar panels.

Atmospheric Pressure (Mars)

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Atmospheric Pressure (Mars)

The pressure on the Martian surface is extremely low, averaging about 600 Pascals (or 6 millibars), less than 1% of Earth's pressure at sea level. It is too low for liquid water to be stable on the surface.

Artemis Program

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Artemis Program

NASA's successor lunar exploration program to Apollo. Its goal is to establish a sustainable human presence on the Moon (including the Gateway station) as a "proving ground" for the technologies and operations needed to send humans to Mars.

Mariner Program

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Mariner Program

A series of NASA robotic missions (in the 1960s and 1970s) designed for planetary exploration. Mariner 4 conducted the first successful flyby of Mars in 1965, and Mariner 9 was the first spacecraft to orbit another planet (Mars) in 1971.

Mars Program (Soviet)

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Mars Program (Soviet)

A series of Soviet missions to Mars lasting from 1960 (Mars 1M) to the 1970s. It included the first soft landing (Mars 3) and the first orbiter (Mars 2 & 3). They were pioneers despite numerous failures.

Viking Program

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Viking Program

A series of two NASA missions (Viking 1 and 2) in 1976, each consisting of an orbiter and a lander. They were the first missions to successfully land on Mars and conduct direct biological experiments to search for life.

Zond Program

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Zond Program

A Soviet space program (1964-1970). While primarily focused on the Moon, the first missions (Zond 1, 2, 3) were intended as Venus and Mars flyby attempts, though communications failed en route.

Promethei Terra

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Promethei Terra

A vast highland region in the southern hemisphere, near the pole. It is a heavily cratered region that shows extensive glacial modification and ice deposits.

Solar Electric Propulsion (SEP)

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Solar Electric Propulsion (SEP)

A very low-thrust but extremely high-efficiency propulsion system. It uses large solar arrays to generate electricity, which then ionizes a propellant (like xenon) and accelerates it. Ideal for robotic cargo missions or the lunar Gateway, but not for rapid crewed missions.

Nuclear Thermal Propulsion (NTP)

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Nuclear Thermal Propulsion (NTP)

A type of rocket propulsion that uses a nuclear fission reactor to heat a liquid propellant (like hydrogen) to extreme temperatures, expanding it through a nozzle. It offers much higher efficiency (Specific Impulse) than chemical rockets, shortening the travel time to Mars.

Planetary Protection (Forward)

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Planetary Protection (Forward)

The principle of protecting a solar system body (like Mars) from biological contamination from Earth. It involves the rigorous sterilization of spacecraft, especially those searching for life (Astrobiology).

Planetary Protection (Backward)

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Planetary Protection (Backward)

The principle of protecting Earth's biosphere from potential contamination by extraterrestrial life (if it exists) brought back by a sample return mission or a returning crew from Mars.

Ground-Penetrating Radar (GPR)

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Ground-Penetrating Radar (GPR)

An instrument (like RIMFAX on the Perseverance rover or MARSIS on Mars Express) that sends radio waves into the subsurface to map geological structures, detect layers of water ice, or saline aquifers beneath the surface.

Galactic Cosmic Radiation (GCR)

Human Exploration & Life Support
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Galactic Cosmic Radiation (GCR)

A flux of high-energy subatomic particles (primarily protons and heavy atomic nuclei) originating from outside our solar system. It represents one of the greatest health risks to astronauts on interplanetary missions.

Sabatier Reaction

Human Exploration & Life Support
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Sabatier Reaction

A key chemical process for ISRU. It uses a catalyst to react hydrogen (H2, brought from Earth) with carbon dioxide (CO2, from Mars's atmosphere) to produce methane (CH4, rocket fuel) and water (H2O).

Deep Space Network (DSN)

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Deep Space Network (DSN)

A global system of large radio antennas (in the USA, Spain, and Australia) operated by NASA. It is fundamental for two-way communication and tracking of interplanetary missions, including all active missions at Mars.

Storm Shelter (Radiation)

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Storm Shelter (Radiation)

A heavily shielded area within a transit spacecraft or Mars habitat (often using water or polyethylene). The crew retreats to this shelter during a Solar Particle Event (SPE) to minimize acute radiation exposure.

Tharsis Region

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Tharsis Region

A vast volcanic province at the Martian equator. It is a massive "bulge" (thousands of km wide) that hosts the largest volcanoes in the Solar System, including Olympus Mons. Its immense weight is thought to have influenced the planet's geology and rotation.

Regolith

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Regolith

A layer of loose, heterogeneous material (composed of dust, rock fragments, and other materials) that covers the solid bedrock of a planet, moon, or asteroid. Studying Martian regolith is key to understanding the planet's geology and for resource utilization.

Communications Relay

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Communications Relay

An essential function performed by Mars orbiters (like MRO, TGO, and Mars Express). They relay the large volume of science data from rovers and landers on the surface (which have small antennas) back to Earth (which has large DSN antennas).

REMS (Rover Environmental Monitoring Station)

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REMS (Rover Environmental Monitoring Station)

The weather station aboard the Curiosity rover. Similar to MEDA, it measures daily atmospheric conditions in Gale Crater, providing crucial context for geology and habitability.

Psychological Resilience

Human Exploration & Life Support
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Psychological Resilience

The ability of an individual or crew to maintain mental health, performance, and social cohesion under the extreme stress of isolation, confinement, and danger of a Mars mission. It is a key selection criterion for astronauts.

Communication Delay

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Communication Delay

The time it takes for a radio signal to travel between Earth and Mars. It varies significantly (from ~3 to 22 minutes one-way) depending on the planets' orbital positions. This delay prevents real-time control (like a joystick) and necessitates a high degree of autonomy for rovers and crewed missions.

Supersonic Retropopulsion

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Supersonic Retropopulsion

A landing technique (EDL) that involves firing rocket engines *while* the spacecraft is still traveling at supersonic speeds. It is a key technology (tested by SpaceX) needed to land very heavy payloads (like human habitats) on Mars.

Spaceflight-Associated Neuro-ocular Syndrome (SANS)

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Spaceflight-Associated Neuro-ocular Syndrome (SANS)

A medical condition affecting astronauts on long-duration missions (ISS). Microgravity causes changes in cerebrospinal fluid pressure, affecting the optic nerve and potentially causing vision problems. It is a key health risk for a trip to Mars.

Circadian Rhythm

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Circadian Rhythm

The internal ~24-hour biological clock that regulates sleep-wake cycles. On Mars, the solar day ("Sol") is 24 hours and 39.5 minutes long. Adapting astronauts' circadian rhythm to this longer "Sol" is a human health and psychology challenge.

Rover

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Rover

A robotic exploration vehicle designed to move across the surface of a planet or celestial body. Rovers, such as Curiosity or Perseverance, are equipped with scientific instruments to analyze the environment in-situ.

Zhurong Rover

Missions & Programs
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Zhurong Rover

China's first Mars rover, a component of the Tianwen-1 mission (landed 2021). It explored the Utopia Planitia plain, studying surface geology and searching for subsurface water ice with a ground-penetrating radar.

RTG (Radioisotope Thermoelectric Generator)

Technology & Instruments
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RTG (Radioisotope Thermoelectric Generator)

A non-solar power source. It uses the heat generated by the radioactive decay of plutonium-238 to produce electricity. It is the power source for the Curiosity and Perseverance rovers, allowing them to operate at night and during the Martian winter without relying on solar panels.

Fast Transit Path (Conjunction-class)

Human Exploration & Life Support
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Fast Transit Path (Conjunction-class)

A type of crewed mission trajectory that uses a Venus flyby or a higher propellant (delta-v) expenditure to drastically shorten the transit time to Mars (e.g., 6 months instead of 9), reducing crew exposure to radiation and microgravity.

Cleanroom (Aerospace)

Technology & Instruments
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Cleanroom (Aerospace)

A spacecraft assembly environment with extremely strict control over particulates (dust, microbes). It is essential for planetary protection (avoiding contamination of the craft) and for ensuring sensitive instruments do not fail.

SAM (Sample Analysis at Mars)

Technology & Instruments
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SAM (Sample Analysis at Mars)

The main chemical laboratory aboard the Curiosity rover. It is an instrument suite (mass spectrometer, gas chromatograph) designed to analyze the composition of soil, rocks, and the atmosphere, searching for organic compounds.

SEIS (Seismometer)

Technology & Instruments
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SEIS (Seismometer)

The primary instrument on the InSight mission (Seismic Experiment for Interior Structure). A highly sensitive seismometer designed to detect "marsquakes" and analyze how seismic waves travel through the planet.

Serpentinization

Planetary Science & Geology
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Serpentinization

An exothermic geological process where olivine-rich rocks react with water. This process releases heat and hydrogen (H2), creating an energy gradient that can be used by microbial life (chemosynthesis). It is a potential source of non-biological methane on Mars.

SHERLOC

Technology & Instruments
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SHERLOC

Acronym for "Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals". An instrument on Perseverance's arm that uses ultraviolet Raman spectroscopy to search for minerals and organic compounds, being key in the search for biosignatures.

Opaline Silica

Planetary Science & Geology
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Opaline Silica

A non-crystalline, hydrated form of silica (similar to opal). Its discovery by the Spirit rover in Gusev Crater was significant, as on Earth this mineral is commonly associated with hot springs or volcanic activity altering rocks in the presence of water.

Sinai Planum

Planetary Science & Geology
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Sinai Planum

A high volcanic plateau in the Tharsis region, located just south of the Valles Marineris canyon system.

Sample Caching System

Technology & Instruments
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Sample Caching System

The complex robotic system (aboard Perseverance) that includes a drill, a bit carousel, and sealed titanium sample tubes. Its function is to extract rock cores, assess them, and hermetically seal them for future collection.

Attitude Control System (ACS)

Technology & Instruments
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Attitude Control System (ACS)

The system that controls a spacecraft's orientation (attitude) in space. It uses thrusters, reaction wheels, or gyroscopes to point antennas at Earth, solar panels at the Sun, or scientific instruments at their targets.

Rocker-Bogie Suspension System

Technology & Instruments
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Rocker-Bogie Suspension System

A robotic mobility system with six independent wheels, used on all NASA Mars rovers (from Sojourner to Perseverance). It is designed to maintain constant contact of all wheels with the terrain, allowing the rover to stably traverse large obstacles (like rocks).

Sol (Martian Day)

Planetary Science & Geology
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Sol (Martian Day)

The name for a solar day on Mars. It is the time period between two successive passages of the Sun over the local meridian. One Sol lasts 24 hours, 39 minutes, and 35.2 seconds.

Solis Planum

Planetary Science & Geology
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Solis Planum

An elevated plateau south of Valles Marineris, known as the "Eye of Mars" (Oculus) due to its dark, round shape. It is a region that experiences intense dust storms.

Space Launch System (SLS)

Technology & Instruments
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Space Launch System (SLS)

NASA's super heavy-lift launch vehicle, the core component of the Artemis program. It is designed to launch the Orion spacecraft and other large payloads (like habitats) needed for crewed missions to the Moon and, eventually, to Mars.

Spirit (MER-A)

Missions & Programs
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Spirit (MER-A)

The twin rover of Opportunity (MER). It landed in Gusev Crater. It found evidence of a wet, non-acidic past in the "Columbia Hills," including pure silica deposits pointing to hydrothermal springs.

Starship (SpaceX)

Technology & Instruments
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Starship (SpaceX)

A next-generation, fully reusable space vehicle developed by SpaceX. It is designed to carry crew and large amounts of cargo to Earth orbit, the Moon, and Mars, with the goal of enabling Mars colonization.

Sublimation

Planetary Science & Geology
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Sublimation

The physical process of a substance transitioning directly from a solid state to a gas state, without passing through the liquid phase. On Mars, this process dominates the CO2 (dry ice) cycle in the seasonal polar caps.

Hydrated Sulfates

Planetary Science & Geology
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Hydrated Sulfates

A group of minerals (like gypsum and jarosite) that have water molecules incorporated into their crystal structure. Their widespread discovery on Mars (by Opportunity and orbiters) is irrefutable proof of an aqueous, though likely acidic, past.

SuperCam

Technology & Instruments
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SuperCam

An advanced version of ChemCam, located on Perseverance's mast. It combines LIBS with Raman and visible-infrared spectroscopy to determine not only chemical composition, but also mineralogy and the presence of organic molecules from a distance.

Syrtis Major Planum

Planetary Science & Geology
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Syrtis Major Planum

A distinct "dark spot" (a low-albedo feature) visible from Earth. It is an ancient, low-relief shield volcano composed of dark basaltic lavas.

Sampling Drill (Rover)

Technology & Instruments
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Sampling Drill (Rover)

A drilling system (like on Curiosity or Perseverance) designed not just to grind, but to extract a rock core (Perseverance) or a powder (Curiosity) and transfer it to the analytical labs inside the rover.

Terra Cimmeria

Planetary Science & Geology
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Terra Cimmeria

A large highland region in the southern hemisphere of Mars. It is one of the oldest areas on the planet and is notable for hosting Mars's strongest crustal magnetic anomalies, remnants of the ancient global magnetic field.

Terra Sabaea

Planetary Science & Geology
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Terra Sabaea

An ancient, dark (low albedo) highland region stretching along the equator. It is known for its strong magnetic anomalies and complex geological history.

Terra Sirenum

Planetary Science & Geology
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Terra Sirenum

A densely cratered southern highland region. This area also contains strong magnetic anomalies and is of interest for studying groundwater history, showing evidence of valleys and lake basins.

Terraforming

Human Exploration & Life Support
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Terraforming

The (currently hypothetical) process of planetary engineering designed to deliberately modify the atmosphere, temperature, topography, or ecology of a planet, moon, or other body to make it habitable for human life.

Chaos Terrain

Planetary Science & Geology
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Chaos Terrain

A unique geological landscape on Mars, characterized by a jumbled, disordered set of blocks, mesas, and valleys. It is thought to form from the sudden collapse of terrain following the massive release of groundwater (outflow floods).

TES (Thermal Emission Spectrometer)

Technology & Instruments
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TES (Thermal Emission Spectrometer)

An instrument on Mars Global Surveyor that measured infrared radiation (heat) emitted from the Martian surface. This allowed mapping mineral composition (like the hematite at Meridiani) and atmospheric temperatures.

Thaumasia Planum

Planetary Science & Geology
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Thaumasia Planum

A vast highland plateau that forms the southern border of the Tharsis region and Valles Marineris.

Tianwen-1

Missions & Programs
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Tianwen-1

China's first interplanetary mission to Mars, launched in 2020. It achieved a trifecta: inserting an orbiter, deploying a lander, and operating the Zhurong rover on the Martian surface.

Global Dust Storm

Planetary Science & Geology
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Global Dust Storm

A planet-scale meteorological event on Mars where dust is lifted to enshroud the entire atmosphere, blocking sunlight. These storms are a hazard for solar-powered missions (a 2018 global storm ended Opportunity's mission).

xEMU Suit

Human Exploration & Life Support
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xEMU Suit

Acronym for "Exploration Extravehicular Mobility Unit". NASA's next-generation spacesuit designed for the Artemis program. Unlike Apollo or ISS suits, it is optimized for mobility on planetary surfaces (walking, kneeling, sampling) and will protect astronauts on the Moon and Mars.

Minimum Energy Transfer

Technology & Instruments
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Minimum Energy Transfer

The general term for the most fuel-efficient trajectory between two orbiting bodies, such as the Hohmann Transfer Orbit. It is the standard path for robotic cargo missions to Mars, though crewed missions may opt for faster, higher-energy trajectories.

Utopia Planitia

Planetary Science & Geology
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Utopia Planitia

A vast plain and impact basin in Mars's northern hemisphere. It is the landing site for the Viking 2 mission (1976) and the Zhurong rover (2021). It is suspected to host large quantities of subsurface water ice.

Valles Marineris

Planetary Science & Geology
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Valles Marineris

An immense canyon system, one of the largest in the Solar System. It stretches for over 4,000 km along the Martian equator. Unlike the Grand Canyon (eroded by water), Valles Marineris is thought to be a large tectonic fault system formed by crustal stretching.

Vastitas Borealis

Planetary Science & Geology
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Vastitas Borealis

The name for the vast lowlands surrounding the Martian north pole. It is the largest low-elevation region on the planet. It is the site of the "Boreal Ocean" hypothesis, suggesting these plains hosted an ocean in the past.

Mars Ascent Vehicle (MAV)

Technology & Instruments
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Mars Ascent Vehicle (MAV)

A crucial component for a sample return or crewed mission. It would be a rocket launched from the Mars surface to place samples (or crew) into Mars orbit, where it would rendezvous with an Earth return vehicle.

Pressurized Rover

Human Exploration & Life Support
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Pressurized Rover

A vehicle concept for human exploration. It would be a mobile habitat, similar to an RV, allowing astronauts to conduct multi-day or multi-week EVAs far from the main base, living inside the rover without spacesuits.

Launch Window

Technology & Instruments
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Launch Window

The specific period of time, a few weeks long, during which a mission to Mars must launch from Earth to follow the most energy-efficient trajectory (like a Hohmann transfer). These windows open every 26 months, aligning with the Mars Opposition.

Solar Wind

Planetary Science & Geology
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Solar Wind

A constant stream of charged particles (plasma) ejected from the Sun's corona. At Mars, lacking a global magnetic field, the solar wind interacts directly with the upper atmosphere, stripping away ions and contributing to atmospheric loss.

Yardang

Planetary Science & Geology
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Yardang

A geological rock formation, often streamlined, carved by wind and dust abrasion. They are common on Mars (especially in the Medusae Fossae Formation) and indicate the predominant wind direction over eons.