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Robert Walker
Yes high speed winds. But because the atmosphere is so thin, then it hasn't got much force.

The highest speeds are probably the speeds in the dust devils. Can be up to 45 meters per second or 162 kilometers per hour.

HiRISE Clocks Hurricane Speed Winds In Martian Dust Devils

However, the density of the Mars atmosphere is far less than Earth's. This varies between day and night and between summer and winter and depending on altitude. It is greatest at the bottom of the Hellas basin in the northern summer.

Roughly though, it is about 1% of Earth's, so the winds have a hundredth of the energy they have on Mars for the same velocity.

Or, since kinetic energy = mass * velocity squared, that hundredth of the mass has the same kinetic energy as a wind on Earth at a tenth of the velocity.

So - that 162 kilometers per hour on Mars is roughly equivalent in its effect to 16.2 kilometers per hour on Earth in terms of its kinetic energy.

So - we don't need to take especial care to protect our rovers from the winds. Even the strongest winds won't be able for instance to blow away significant parts of the rover or damage the solar panels.

As an example of this, the parachutes from our landers on Mars remain on the surface just where they landed for years on end.

This image may identify one of the parachutes of Beagle 2 which has remained undisturbed on the surface for about a decade. You wouldn't expect it to be moved by the Martian winds as they are just too weak for this.Beagle 2 spacecraft found intact on surface of Mars after 11 years

Indeed the dust devils have proved to be useful by cleaning the dust from the solar panels.

You get the impression that Mars winds must be pretty strong because of the dust storms. However the Mars dust is far finer than dust on Earth. The average dust particle size is of the order of 1.6 microns.
Dust on Mars - University of Copenhagen

You would need a microscope or hand lens to see the individual particles. This Mars dust is similar in size to the dust in tobacco smoke and average sized bacteria. Particle Sizes

MYSTERY OF MOVING SAND DUNES ON MARS


Mars has sand dunes, and surprisingly, about the same amount of sand moves on Mars as moves on similar sand dunes on Earth. You'd think, with the winds only about a tenth of the energy, that the sand would hardly move at all. But not just ripples, even huge sand dunes move:

Advancing Dune in Nili Patera, Mars. Back-and-forth blinking of this two-image animation shows movement of a sand dune on Mars. This discovery shows that entire dunes as thick as 200 feet (61 meters) are moving as coherent units across the Martian landscape. The sand dunes move at about the same flux (volume per time) dunes in Antarctica. This was unexpected because of the thin air and the winds which are weaker than Earth winds. It may be due to "saltation" - balistic movement of sand grains which travel further in the weaker Mars gravity. See NASA Spacecraft Detects Changes in Martian Sand Dunes - Mars Reconnaissance Orbiter

The lee fronts of the dunes in this region move on average 0.5 meters per years (though the selection may be biased here as they only measured dunes with clear lee edges to measure) and the ripples move on average 0.1 meters per year.

Anyway - it turned out the answer is probably due to the lower Mars gravity as that caption says:

LARGER DUST GRAINS ON MARS MOVE THROUGH SALTATION - BOUNCING OVER THE SURFACE


Larger particles in the dunes move through "saltation" where the particles do not get taken right up into the atmosphere but instead move on ballistic trajectories - of a few hundred meters (far further than on Earth) - this moves particles of up to mms scale that are far too large to be lifted up into the atmosphere. Giant saltation on Mars

So this is what forms the dunes on Mars. The huge moving sand dunes there are a result of the lower gravity, which lets the grains of sand move more easily without ever being taken up into the atmosphere. So that again gives an impression that the winds on Mars are stronger than they are.

DUST DEVILS


The dust devils on Mars are very impressive, comparable to the Earth ones. But the dust is far lighter  - the Martian dust is comparable in particle size to cigarette smoke.



 Here is a 3D zoom in and reconstruction of one:

More about them:



Trails left by dust devils on Mars


DUST STORMS


Then you get global dust storms, which are strongest every two years when Mars is closest to the sun (perihelion).

Mars Dust Storms

STRONGER WINDS WHEN MARS ATMOSPHERE GETS THICKER


Also, at times, depending on its axial tilt, over geological timescales, the Mars atmosphere gets somewhat thicker (due to CO2 released from the polar caps), and then its winds would be a little more powerful.

See also:
How do Mars rovers stay upright on their wheels in severe storms? Has there ever been any incident where something toppled the rovers?

(I just copied my answer over here and edited it some).

About the Author

Robert Walker

Robert Walker

Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.
Studied at Wolfson College, Oxford
Lives in Isle of Mull
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