iTechGuides is reader-supported. When you buy through links on our site, we may earn an affiliate commission. As an Amazon Associate I earn from qualifying purchases. Learn more
Scientists study Martian clouds by combining three kinds of evidence: orbital cameras and atmospheric sensors that survey large regions, laser altimetry that can reveal cloud layers even in polar darkness, and landers or rovers that repeatedly watch the sky from one surface location. Atmospheric models then test whether the observed temperature, pressure, water vapor, dust and altitude could produce water-ice clouds, carbon-dioxide ice clouds or dust structures. No single spacecraft measures every property, so the useful result comes from matching each instrument’s view with the others.
What scientists need to measure
A cloud observation has several separate questions hidden inside it. Researchers want to know where a feature is, how high it extends, whether it is made of water ice, carbon-dioxide ice or dust, how its particles grow and move, and how long it survives. Brightness or color alone rarely answers all of those questions. A camera may show a plume’s shape and motion, while an infrared instrument can measure the atmospheric conditions that make a particular cloud possible.
| # | Preview | Product | Price | |
|---|---|---|---|---|
| 1 |
|
The Exploration of Mars | $29.95 | Buy on Amazon |
| 2 |
|
A Science Strategy for the Human Exploration of Mars | $40.00 | Buy on Amazon |
| 3 |
|
Red Mars (Mars Trilogy) | $12.70 | Buy on Amazon |
| 4 |
|
Green Mars (Mars Trilogy) | $12.90 | Buy on Amazon |
| 5 |
|
The Last Dragon on Mars (The Dragonships Series) | $8.69 | Buy on Amazon |
Scientists therefore compare observations with atmospheric predictions. NASA describes Martian cloud research as a hierarchy of equations, circulation models and measurements from orbiters, landers and rovers. For water-ice clouds, the models account for crystals nucleating on airborne dust particles. If a model predicts that water should freeze at a certain altitude and time, an image or vertical profile can test that prediction rather than being interpreted in isolation.
Crashes, No Sound, or Screen Glitches?
Random freezes, missing sound and display glitches usually trace back to one bad driver. Find and replace yours safely.Free scan · under a minuteWindows Errors? Fix Them Before They Spread
Repair common Windows errors and clear accumulated junk for a smoother, more stable PC - no reinstall needed.Free scan · no reinstallHow orbiters observe clouds from above
Orbital cameras map appearance and motion
Cameras provide the most intuitive evidence: a cloud’s outline, brightness, color, direction of travel and change over time. A wide-angle camera looking toward the Martian limb—the visible edge of the planet—can catch high-altitude clouds or detached dust structures that would be difficult to recognize in a narrow view of the surface.
#1 Best Overall
The Visual Monitoring Camera (VMC) on ESA’s Mars Express is an example of an instrument whose scientific role changed over time. It was installed originally to confirm the separation of the Beagle 2 lander, then repurposed for atmospheric observations. ESA’s catalogue contains more than 21,000 VMC images collected from 2007 through 2016. Researchers selected 300 images as cloud or dust candidates and examined 18 events in depth. Most of those 18 events were interpreted as water-ice clouds; one was interpreted as a dust storm. Atmospheric predictions and other spacecraft observations helped distinguish the likely cloud type and relate visibility to local time and temperature.
Infrared sounders build vertical profiles
NASA’s Mars Reconnaissance Orbiter carries the Mars Climate Sounder (MCS), which looks toward the horizon and samples the atmosphere in vertical slices. MCS uses nine channels spanning visible, near-infrared and thermal-infrared wavelengths. Its visible/near-infrared channel helps characterize how sunlight interacts with the atmosphere and surface. Thermal-infrared channels measure properties including temperature, pressure, water vapor and dust.
The instrument samples at roughly 5-kilometer vertical increments. Those measurements are combined into daily, three-dimensional global weather maps covering both day and night. The maps let scientists ask whether an apparent cloud sits in a cold, moist layer, whether dust is present below or within it, and how the layer changes across a region.
Quick wins for a faster PC:
Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →Clear out junk files and repair common Windows errorsFree Scan →Scan for outdated or missing drivers - takes under a minuteDriver Scan →Orbital timing limits what MCS can see at a particular local time. JPL describes typical MRO MCS profiles as occurring around 3 a.m. and 3 p.m. local time, except near the poles. A cloud that forms shortly before sunrise may therefore be missed by one spacecraft’s regular sampling even when another mission can observe it.
Laser altimetry detects clouds without visible sunlight
The Mars Orbiter Laser Altimeter (MOLA) on Mars Global Surveyor was designed to measure surface topography, but its laser pulses also returned from atmospheric cloud layers. MOLA detected clouds at heights up to about 20 kilometers. Because it measured laser returns rather than relying on reflected sunlight, it could determine vertical cloud structure during polar winter night, when visible-light imaging is unavailable.
MOLA’s global cloud measurements began in March 1999 and continued for about 1.25 Martian years. This record illustrates why an instrument built for one purpose can become valuable to atmospheric science: the return signal contained information about suspended particles above the surface.
What landers and rovers add
A lander or rover cannot provide the global coverage of an orbiter. Its camera sees only the sky above one landing site, and local terrain can block part of the horizon. The advantage is continuity: a surface mission can look repeatedly at the same patch of sky at selected times and seasons, often with the same camera and viewing geometry.
The Tool Desk
Outbyte Driver Updater FREEScan for outdated or missing drivers - takes under a minuteDriver Scan →Outbyte PC Repair FREEClear out junk files and repair common Windows errorsFree Scan →Pathfinder established a surface record
NASA reports that twilight clouds were first seen from the surface by the Pathfinder mission in 1997. A repeated surface sequence can show how a cloud’s brightness, color and texture change over minutes or across seasons, information that a widely spaced orbital pass may not provide.
Rank #3
Curiosity follows predictable seasonal clouds
Curiosity began observing Martian clouds in 2019 and has recorded iridescent clouds. Because similar clouds recur at a predictable time of year, the team can plan observations in advance. Atmospheric scientist Mark Lemmon described the pattern to NASA: “Now it’s become so predictable that we can plan our shots in advance; the clouds show up at exactly the same time of year.” Those images help investigators study particle size and growth at a fixed location.
That local strength has a strict boundary. A cloud observed over Curiosity’s landing site should not be assumed to occur everywhere on Mars. Surface observations provide detailed context for one place and season; orbital measurements are needed to determine how widespread a phenomenon is.
Orbiters versus landers and rovers
| Capability | Orbiters | Landers and rovers |
|---|---|---|
| Spatial coverage | Can survey broad regions and, with suitable instruments, produce global maps | Detailed observations from one fixed or slowly moving surface location |
| Vertical atmospheric information | Sounders and laser altimeters can measure or infer cloud layers at different heights | Usually infer overhead conditions from local images and atmospheric sensors |
| Time-of-day access | Controlled by orbit, instrument pointing and repeat cycle; MCS commonly samples near 3 a.m. and 3 p.m. local time away from the poles | Can be scheduled for local sunrise, twilight, afternoon or night when power and operations permit |
| Repeat observations | Repeated passes build regional and seasonal records, but a transient event can fall between passes | Can watch the same sky repeatedly and target a known seasonal recurrence |
| Best evidence | Distribution, altitude, temperature, water vapor, dust, motion and large-scale evolution | Local appearance, color, particle-growth clues and short-term changes |
| Main limitation | Orbital geometry and wavelength coverage leave gaps in local time or cloud properties | No direct global context; a local cloud is not automatically a planet-wide event |
The step-by-step workflow for identifying a Martian cloud
- Find a candidate feature. A camera sequence may reveal a bright limb cloud, an elongated plume or a detached structure. A laser return or infrared profile may show a layer even when the feature is not obvious in visible images.
- Measure its location and height. Researchers use spacecraft viewing geometry, repeat images and vertical profiles to estimate latitude, longitude, altitude and movement. MCS’s approximately 5-kilometer sampling increments provide a vertical framework; MOLA supplies an independent type of cloud-height evidence for some layers.
- Check atmospheric conditions. Temperature, pressure, water vapor and dust are compared with the phase conditions required for water-ice or carbon-dioxide ice. A dust-rich signal may indicate a dust structure rather than a condensed cloud.
- Compare wavelengths and instruments. Visible and near-infrared brightness, thermal-infrared emission, laser returns and independent spacecraft images respond differently to particles and gas. Agreement between them strengthens an interpretation; disagreement identifies uncertainty that requires modeling.
- Follow the feature through time. Scientists measure whether it grows, drifts, detaches, fades or evaporates. Orbital passes supply regional context, while a lander or rover can fill in rapid local changes.
- Test a physical explanation with models. Atmospheric models examine winds, temperature gradients, dust transport, condensation and evaporation. The preferred explanation is the one that accounts for the observed location, altitude, timing and evolution without treating a single image as proof of composition.
Case study: the elongated morning cloud over Arsia Mons
The cloud over Arsia Mons demonstrates why local time and coordinated instruments matter. ESA reports that it begins growing before sunrise on the volcano’s western slope. It expands westward for about two and a half hours at an altitude of around 45 kilometers, then detaches and is carried farther west by high-altitude winds before evaporating later in the morning. Its reported growth rate exceeds 600 kilometers per hour.
Do these 3 things before closing this tab:
1Clear out junk files and repair common Windows errors2Fix the driver behind crashes, sound loss and screen glitches3Repair Windows errors before they cause bigger problemsResearchers combined Mars Express VMC images with measurements from Mars Express’s OMEGA and HRSC instruments, NASA’s MAVEN and Mars Reconnaissance Orbiter, Viking 2 and India’s Mars Orbiter Mission. The wide monitoring view helped establish when the plume should appear; a higher-resolution instrument could then investigate the predicted event. The spacecraft did not all see the same moment, because their orbits and viewing geometries differed. Mars Express was especially useful because its geometry allowed observations during the morning hours when many other Mars missions could not view that surface region.
Rank #4
The sequence—growth before sunrise, rapid westward extension, detachment, wind transport and later evaporation—also separates a transient atmospheric process from a stationary bright marking on the volcano. Without time-resolved observations and wind information, the same feature could be misclassified or its speed greatly underestimated.
Case study: what the 2019 regional dust storm revealed
A regional dust storm in January and February 2019 shows the value of simultaneous measurements at different altitudes. NASA’s Mars Reconnaissance Orbiter measured temperature, dust and water ice up to approximately 100 kilometers altitude. ESA’s Trace Gas Orbiter measured water vapor and ice across the same broad altitude range. NASA’s MAVEN observed hydrogen in the upper atmosphere.
NASA reported that the middle atmosphere contained ten times more water after the storm began and that upper-atmosphere hydrogen increased by 50 percent during the storm. The combined record connected dust-related atmospheric warming with the loss of some ice clouds, the transport of water to higher altitudes and an increase in hydrogen in the upper atmosphere. A camera alone could have shown that dust obscured the sky; the coordinated profiles showed how the storm altered the vertical water cycle and upper-atmosphere escape processes.
Recommended Free Tools
How scientists distinguish cloud types
Water-ice clouds
Water-ice clouds form when atmospheric water reaches temperatures and pressures that allow ice crystals to persist. On Mars, NASA describes the crystals as nucleating on airborne dust particles. Their identification is strengthened when images, temperature profiles, water-vapor measurements and model predictions agree.
Best Value
Carbon-dioxide ice clouds
Carbon-dioxide ice clouds require much colder conditions than water-ice clouds and are expected in particular high-altitude or polar environments. The relevant question is not simply whether a white feature is visible, but whether the measured pressure and temperature permit carbon dioxide to condense at that height and season.
Dust structures
Dust storms and detached dust layers can resemble clouds in a camera image. Infrared dust measurements, visible-light behavior, altitude and storm evolution help separate airborne mineral dust from ice. The Mars Express VMC sample illustrates this caution: of the 18 events examined in depth, most were interpreted as water-ice clouds and one as a dust storm, using atmospheric predictions and other spacecraft data rather than appearance alone.
Why no single mission is enough
Each mission samples a different combination of wavelength, altitude, field of view and local time. A camera is strong at morphology but may not identify composition. A sounder provides atmospheric structure but samples along an orbital track. A laser altimeter can reveal vertical layers in darkness but does not replace broad spectral or chemical measurements. A rover can return a long local sequence but cannot establish global frequency.
Scientists therefore treat missions as complementary, not interchangeable. They align observations by location, season and local time, then use models to bridge gaps between measurements. When an event is short-lived—such as the Arsia Mons plume—orbital geometry can determine whether it is seen at all. When an event changes the whole atmospheric column—such as the 2019 dust storm—coordinated instruments are needed to connect clouds near the surface with water and hydrogen higher up.
What cloud observations tell us about Mars
- Weather and circulation: Cloud motion reveals wind direction and speed, while cloud growth and decay expose vertical transport and temperature changes.
- The water cycle: Water-ice clouds mark where vapor condenses, and upper-atmosphere measurements show whether storms move water to altitudes where it can be lost.
- Dust–atmosphere feedback: Dust absorbs sunlight and warms the atmosphere, changing where ice clouds can survive and how water is redistributed.
- Seasonal predictability: Repeated rover observations, such as Curiosity’s twilight-cloud record, reveal when local conditions recur.
- Atmospheric escape: MAVEN’s hydrogen measurements during the 2019 storm linked a lower-atmosphere weather event with changes in the upper atmosphere.
Interpreting a new image responsibly
When a new Martian sky image appears, the safest conclusion is usually descriptive: a bright or colored feature was observed at a stated time and location. Composition requires additional evidence. Check the spacecraft’s local-time access, the feature’s estimated altitude, nearby temperature and dust measurements, and whether a model predicts condensation there. Also check whether the apparent change is real motion or an effect of lighting, camera exposure or viewing angle.
The strongest claims come from converging records: repeated images, an atmospheric profile, an independent mission and a model that reproduces the event’s timing and evolution. That approach turns a striking photograph into a measurement of Martian weather.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
