Perseverance Debris Accidentally Became a Mars Experiment

NASA sent the Perseverance rover to Mars to search for signs of ancient life.

But some of the mission's most revealing geology may have come from hardware that was never intended to do science at all.

During Perseverance's arrival at Mars in February 2021, the spacecraft discarded two 77-kilogram tungsten ballast masses. Its much larger cruise stage also separated and fragmented before pieces reached the surface.

The falling hardware slammed into Mars at several kilometers per second, producing five fresh craters roughly 70 kilometers northwest of Jezero crater.

Normally, spacecraft debris would simply be catalogued as an unavoidable consequence of landing.

Instead, scientists realized they had accidentally created something extremely valuable:

a controlled planetary impact experiment.

Unlike a natural meteorite, researchers knew what at least two of the impactors were made from. They knew their mass. They could reconstruct their trajectory, speed and impact angle.

That allowed them to work backward from the resulting craters and ask a surprisingly difficult question:

How strong is the Martian ground?

The answer, published in Geophysical Research Letters in September 2026, was unexpected.

Three-dimensional impact simulations indicate that the near-surface material had a cohesion of only about 7 ± 1.5 kilopascals—consistent with weak Martian regolith.

Just as importantly, the experiment showed that some conventional formulas used to predict crater sizes can fail dramatically when an ultra-dense object strikes a low-density surface at a very shallow angle.

What began as discarded spacecraft hardware had become a calibration experiment for planetary science.

Perseverance Had to Throw Away Heavy Pieces Before Landing

Landing a one-ton rover on Mars is not simply a matter of pointing a spacecraft toward the ground and slowing down.

Perseverance arrived inside an entry vehicle travelling at enormous speed.

To survive atmospheric entry, steer toward Jezero crater and maintain the correct aerodynamic configuration, the vehicle carried carefully positioned ballast masses.

Two of these were known as Cruise Ballast Mass Devices, or CBMDs.

Each was a dense block of tungsten weighing about 77 to 77.5 kilograms. Tungsten was useful because of its extremely high density, allowing engineers to place substantial mass in a relatively compact object.

The ballast helped establish the spacecraft's center of mass and therefore its lift characteristics during entry.

But before the final descent, those masses were no longer needed.

So the spacecraft released them.

A previous reconstruction of Perseverance's entry found that the two blocks were jettisoned when the spacecraft was still about 1,253 kilometers above Mars and travelling at approximately 4.753 kilometers per second relative to the planet.

That number is important because it is sometimes mistakenly described as the impact speed.

It was the spacecraft's speed around the time the ballast masses were released.

NASA's later trajectory reconstruction estimated that the blocks actually reached the surface at approximately 3.816 kilometers per second, striking at an extremely shallow angle of roughly 10 degrees above the horizontal.

The newer 2026 crater study treats about 4 kilometers per second as the most likely impact speed while also modeling 5 kilometers per second to account for uncertainty associated with the irregular shape and aerodynamic drag of the tungsten blocks.

Either way, these were hypervelocity impacts.

At Several Kilometers Per Second, 77 Kilograms Becomes Enormously Energetic

Seventy-seven kilograms does not sound particularly dramatic.

It is roughly the mass of an adult person.

But impact energy increases with the square of velocity.

A 77-kilogram object moving at around 4 kilometers per second carries hundreds of millions of joules of kinetic energy.

An earlier study examining whether NASA's InSight lander could detect the impacts seismically estimated an energy of around 6 × 10^8 joules for one ballast impact under its reconstructed trajectory.

On Earth, atmospheric drag would strongly affect many falling objects.

Mars has an atmosphere too, but it is much thinner.

A compact piece of tungsten is particularly difficult to slow because it combines high density with a relatively small cross-sectional area.

The result was essentially a man-made meteorite.

And there were two of them.

The Cruise Stage Produced More Craters

The two tungsten weights were not the only hardware headed for the surface.

Perseverance's cruise stage—the structure that had supported the spacecraft during its months-long journey from Earth—had a mass of about 539 kilograms before separation.

Unlike the compact tungsten ballast devices, the cruise stage was a much larger and more fragile structure.

It fragmented.

The 2026 study identified five resolved fresh craters in the relevant region.

Two are interpreted as the best candidates for the nearly identical tungsten ballast impacts.

The other three resolved craters are attributed to fragments of the 539-kilogram cruise stage.

That distinction is important.

It would not be accurate to say that a single intact 539-kilogram object struck the surface and made three craters.

Rather, the cruise stage fragmented during its descent, and separate pieces appear to have created several impact scars.

Researchers also identified smaller dark markings that may represent additional unresolved impacts from still smaller fragments.

Scientists Found Five New Craters Northwest of Jezero

The impact site lies in a scientifically interesting location.

The five identified craters are approximately:

• 70 kilometers northwest of the rim of Jezero crater
• about 80 kilometers south of Hargraves crater
• within terrain associated with valleys that ultimately drain toward the Jezero system

The debris landed near a channel connected with the broader Neretva Vallis watershed—the same regional drainage system that supplied sediments toward the ancient Jezero delta.

This makes the accidental impacts more valuable than they might first appear.

Perseverance is exploring Jezero itself.

But the hardware landed far outside the rover's immediate driving range, in terrain that provides regional geological context for the material transported toward the crater billions of years ago.

In other words, discarded spacecraft components effectively sampled the mechanical behavior of ground in a place the rover could not simply drive over and test.

How Did Scientists Know the Craters Were Created by Perseverance?

Mars is covered in impact craters.

Finding five small holes near the predicted landing zone does not automatically prove that a spacecraft created them.

Researchers therefore relied on before-and-after orbital imaging.

NASA's Mars Reconnaissance Orbiter, or MRO, carries two instruments particularly useful for this work:

the Context Camera, or CTX,

and the High Resolution Imaging Science Experiment, better known as HiRISE.

The research team compared images taken before the Mars 2020 arrival with images captured afterward.

The five craters were absent from available pre-landing imagery.

After Perseverance arrived, the new features appeared with clear crater rims, ejecta and extended changes in surface brightness characteristic of fresh Martian impacts.

HiRISE can resolve the Martian surface at roughly 25 centimeters per pixel under suitable conditions.

That allowed researchers to measure the craters in considerable detail.

The five resolved cavities ranged from approximately:

2.6 meters to 6.3 meters across.

The two craters judged most likely to have been produced by the identical tungsten ballast masses were each about:

3.5 ± 0.5 meters in diameter.

Their similar dimensions became an important clue.

Two identical projectiles arriving with similar speed and angle should create broadly similar craters if they strike comparable material.

The Craters Also Revealed the Direction of Impact

A vertical meteorite impact tends to produce a broadly symmetric crater and ejecta pattern.

But the Perseverance ballast masses were anything but vertical.

They struck Mars at an angle of only about 10 degrees from horizontal.

That is an extremely grazing impact.

Some of the resulting ejecta patterns were correspondingly asymmetric.

Researchers describe butterfly-like ejecta around candidate craters—morphology associated with highly oblique impacts.

The orientation of these deposits, combined with predicted landing ellipses calculated by NASA's trajectory software, helped the researchers determine which two craters most likely belonged to the tungsten blocks.

They ultimately favored craters labelled CBMD-c and CBMD-e.

Both were approximately 3.5 meters wide.

The remaining larger and smaller craters were more consistent with fragments from the cruise stage.

Why These Artificial Craters Are Better Than Ordinary Meteorite Craters

Planetary scientists frequently use impact craters to infer properties of a surface.

The basic idea sounds straightforward.

If you know how much energy struck the ground and you measure the resulting crater, you can infer something about the strength and density of the target material.

The difficulty is that for most natural craters, the most important variables are unknown.

Scientists may not know:

• the meteorite's original mass
• its density
• its exact composition
• its shape
• its impact speed
• its entry trajectory
• its impact angle
• how much material burned up or fragmented in the atmosphere

That creates a huge inverse problem.

You can see the crater.

But you do not necessarily know what produced it.

Perseverance's ballast masses turned that situation around.

The projectiles were engineered objects whose properties were documented before launch.

Researchers knew they were tungsten.

They knew each weighed roughly 77 kilograms.

Mission navigation data constrained where they should land.

Trajectory simulations constrained their speed and angle.

Suddenly the unknown was mostly the ground.

That made these craters unusually powerful scientific probes.

Scientists Expected Standard Crater Physics to Work

Planetary scientists have long used empirical crater-scaling relationships.

These equations are built from laboratory impact experiments, explosions, planetary observations and physical theory.

They allow researchers to estimate how crater dimensions change depending on factors such as:

• projectile size
• projectile density
• target density
• impact velocity
• gravity
• target strength

These scaling laws work remarkably well across many impact scenarios.

But every model has a range where its assumptions remain valid.

The Perseverance impacts pushed those assumptions into an unusual regime.

The projectile was extremely dense.

Tungsten has a density of about 19,250 kilograms per cubic meter.

The modeled Martian regolith had a density of only about 1,590 kilograms per cubic meter.

That means the projectile was more than 12 times denser than its target.

And rather than hitting close to vertically, it arrived at only about 10 degrees.

That combination turned out to matter enormously.

The Conventional Equations Gave the Wrong Answer

When the researchers applied standard crater-scaling relationships to the observed craters, the equations implied an effective target strength of roughly:

50 to 200 kilopascals.

In other words, conventional scaling suggested the ground had to be relatively strong to explain why the craters were only a few meters across.

But sophisticated shock-physics simulations told a very different story.

The researchers used iSALE, a numerical modeling system designed to simulate high-speed impacts.

They first performed two-dimensional simulations across a range of soil strengths.

Then they moved to a full three-dimensional simulation that could better represent the extreme 10-degree impact geometry.

The best-fitting 3D result indicated a target cohesion of:

7 ± 1.5 kilopascals.

That is not hard rock.

It is weak regolith.

And it means the simple scaling equations had effectively made the ground appear at least an order of magnitude stronger than the more realistic modeling suggested.

Why Did the Standard Formula Fail So Badly?

The answer lies in the unusual physics of the collision.

Most laboratory crater-scaling experiments involve projectiles and target materials whose densities are not separated by anything like the tungsten-to-regolith contrast involved here.

Tungsten is extraordinarily dense.

When such a dense projectile hits porous soil at hypervelocity, it does not simply excavate material outward in the way a more conventional impactor might.

It penetrates very deeply.

The 2026 simulations produced unusual, elongated cavities described by the researchers as "carrot-shaped" in their two-dimensional models.

Their depth could exceed their diameter.

Much of the impact energy therefore goes into deep penetration rather than simply widening the visible surface crater.

Add the extremely shallow impact angle and the geometry becomes even more unusual.

A simple scaling law calibrated using more typical impact conditions can therefore badly misinterpret what happened.

The paper concludes that traditional scaling relationships can deviate by an order of magnitude when applied to this combination of:

ultra-high projectile density, low-density regolith and grazing impact angle.

Seven Kilopascals: What Does That Actually Mean?

A kilopascal is a unit of pressure.

One kilopascal equals 1,000 pascals.

So 7 kilopascals corresponds to about 7,000 newtons per square meter of cohesive strength in the model.

For planetary geology, that is weak material.

The authors describe the result as being consistent with Martian regolith rather than competent bedrock.

It is tempting to imagine the material as completely loose beach sand.

The reality is slightly more subtle.

"Cohesion" refers to how strongly the material holds together when there is no confining pressure.

Martian surface material can form crusts or clumps while still possessing surprisingly low mechanical resistance under particular loads.

The most useful conclusion is therefore not that the entire region around Jezero is fluffy dust.

It is that the specific near-surface material sampled by the tungsten impacts behaves mechanically like weak, poorly consolidated regolith.

The Result Matches a Very Different Experiment on Mars

What makes the 7-kilopascal estimate particularly interesting is that another Mars mission had already encountered surprisingly strange soil behavior.

NASA's InSight lander arrived on Mars in 2018 carrying the Heat Flow and Physical Properties Package.

Its most unusual component was a self-hammering probe nicknamed the mole.

The mole was supposed to burrow several meters underground while dragging temperature sensors behind it.

Instead, it became stuck almost immediately.

The problem was not simply that the ground was too hard.

It was stranger than that.

The soil formed a cohesive duricrust that did not collapse around the mole in the way loose sand was expected to.

Because the probe depended on surrounding soil to provide friction against its body, the cavity forming around it deprived the mole of the friction it needed to counteract its hammer recoil.

The result was a device that repeatedly hammered but struggled to move downward.

Later analysis estimated the cohesion of that duricrust at roughly 5.8 to 12 kilopascals, a range overlapping the approximately 7-kilopascal result from the Perseverance impact modeling.

Two completely different experiments therefore point toward similar mechanical properties.

One involved a small hammering probe attempting to dig.

The other involved tungsten blocks crashing into Mars at several kilometers per second.

Yet both revealed surprisingly weak and mechanically unusual near-surface material.

Perseverance's Debris Had Already Been Used for Another Experiment

The 2026 crater study was not actually the first scientific attempt to exploit these impacts.

Scientists realized before Perseverance landed that the tungsten masses would strike Mars with substantial energy.

At the time, NASA's InSight lander was operating approximately 3,450 kilometers away.

InSight carried one of the most sensitive seismometers ever placed on another planet.

Researchers hoped the ballast impacts might generate seismic waves strong enough for InSight to detect.

If they did, the event would have been scientifically extraordinary because scientists would know the precise location and approximate time of the source.

It would effectively be a calibration shot through the Martian crust.

The signal was not detected.

No identifiable seismic wave from Perseverance's entry, descent and landing rose above InSight's detection threshold.

Even that non-detection produced useful science.

Researchers were able to place an upper limit on how efficiently impact energy was converted into seismic energy on Mars and showed that some Earth-derived relationships overpredicted the expected signal.

Five years later, the same discarded hardware yielded another lesson:

not about seismic waves this time, but about the mechanical strength of the ground itself.

A Failed Seismic Experiment Became a Successful Cratering Experiment

There is something beautifully scientific about that sequence.

The first question was:

Can we hear these impacts from thousands of kilometers away?

Answer:

Apparently not.

Then came another question:

Can the craters themselves tell us about Martian geology?

Answer:

Yes.

In fact, they can reveal something that normal meteorite craters cannot easily provide because the projectile properties are so poorly constrained.

This is a reminder that a scientific experiment does not necessarily need to produce the result researchers originally hoped for.

The same physical event can remain scientifically useful years later when new questions, data and modeling techniques emerge.

The Craters Matter Because of Where They Landed

The impacts were not randomly distributed across some irrelevant patch of Mars.

They occurred in terrain connected to the wider watershed surrounding Jezero.

Jezero crater was selected as Perseverance's landing site partly because it once contained a lake.

A river flowed into that lake and built a delta whose sedimentary rocks may preserve evidence about ancient Martian environments.

Material carried into that delta originated in the watershed outside Jezero.

The spacecraft debris landed in geological terrain related to that broader drainage system.

This creates an intriguing link.

Perseverance is physically examining rocks inside and around Jezero.

Meanwhile, its discarded landing hardware has provided mechanical information about terrain tens of kilometers away in the watershed.

The debris therefore gives scientists another way to place the rover's local observations into a larger regional context.

The Five Craters Are Not All Sampling the Same Material

The impact field is also useful because the pieces did not all land on identical geology.

Researchers found that some craters formed in units interpreted as pitted capping material, while others landed in valley fill or loose aeolian deposits associated with dunes.

This difference may explain some of the variation in crater size and ejecta patterns.

For example, the five measured craters ranged from only 2.6 meters across to more than 6 meters even though they formed in the same general impact event.

That does not mean each projectile had the same size.

The cruise stage fragmented.

But variations in target strength, slope and sediment type also influence how impact energy creates a cavity.

One of the candidate tungsten craters lies on a local slope of approximately 18.4 degrees, while the other sits on terrain inclined by about 7.8 degrees.

Even small geographical details matter when trying to reconstruct a collision occurring at several kilometers per second.

Spacecraft Debris Could Become an Intentional Scientific Instrument

The most provocative implication of the study concerns future missions.

Every spacecraft landing on another world has to dispose of mass.

Cruise stages separate.

Balance weights are discarded.

Heat shields fall away.

Descent stages crash.

Traditionally, these components are treated primarily as engineering debris.

But what if mission planners deliberately turned some of them into instruments?

Suppose engineers knew:

the precise mass,

shape,

composition,

release time,

trajectory

and eventual impact speed

of a sacrificial piece of hardware.

If an orbiter photographed the crater afterward, scientists would possess a controlled planetary impact experiment at scales almost impossible to reproduce in laboratories on Earth.

The researchers explicitly argue that future missions could intentionally exploit ballast or other disposable hardware this way.

Rather than simply dropping dead weight somewhere harmless, mission designers could select scientifically interesting impact zones.

The debris could become a probe.

We Have Already Done This Deliberately Elsewhere

Using artificial impacts for planetary science is not a new idea.

NASA and other space agencies have deliberately crashed spacecraft or impactors into planetary bodies before.

Apollo rocket stages were sent into the Moon so seismometers could measure the resulting vibrations.

NASA's LCROSS mission deliberately struck the lunar south polar region in 2009, excavating material that helped confirm water ice.

Japan's Hayabusa2 mission used an explosive device to launch a copper projectile into the asteroid Ryugu, creating an artificial crater and exposing subsurface material.

The difference with Perseverance is that its ballast masses were not designed primarily as scientific impactors.

They existed for flight dynamics.

Only afterward did researchers realize just how scientifically useful their craters could be.

That makes them a particularly attractive model for future missions:

science from hardware the spacecraft needed anyway.

Mars Is an Ideal Place for This Kind of Experiment

Mars may be especially suitable for controlled debris impacts.

It has an atmosphere, but not one dense enough to completely destroy compact high-density projectiles.

It also has extensive orbital imaging.

MRO's HiRISE camera can observe meter-scale craters and ejecta patterns from orbit.

And because small new impact craters form frequently on Mars, scientists already have a mature framework for interpreting fresh crater morphology.

Artificial impactors add one crucial ingredient:

known initial conditions.

If future missions deliberately track discarded components all the way to impact, scientists could build a growing database connecting:

projectile mass,

density,

shape,

speed,

angle,

target geology

and final crater dimensions.

That could improve impact models far beyond what one experiment can accomplish.

Better Crater Models Matter Far Beyond Spacecraft Debris

Why should anyone care whether an equation predicts a 3-meter crater correctly?

Because crater physics is one of planetary science's fundamental tools.

Researchers use craters to infer:

• the ages of planetary surfaces
• the strength of crustal materials
• impactor populations
• subsurface structure
• excavation depth
• geological layering
• the mechanics of asteroid and comet collisions

If scaling relationships behave differently when projectile and target densities are extremely mismatched, that matters for interpreting natural impacts too.

Some iron-rich meteorites, for example, may have much higher densities than the materials they strike.

Similarly, future observations could potentially constrain natural impactors before impact through atmospheric fireballs.

If scientists can reconstruct their trajectories and speeds, those events could begin functioning more like the Perseverance hardware experiment.

The 2026 study specifically points toward extending the methodology to natural impactors once their pre-impact properties can be sufficiently constrained.

The Experiment Also Matters for Future Mars Engineering

Understanding soil strength is not only a geology problem.

Future Mars missions may need to:

drill,

bury cables,

anchor equipment,

build landing pads,

move large vehicles,

excavate regolith,

construct habitats

or extract underground resources.

Each of those tasks depends on mechanical properties of the ground.

Mars has already demonstrated how dangerous assumptions can be.

The InSight mole was designed using expectations about how loose Martian soil would behave around a penetrating probe.

Those assumptions turned out to be wrong enough to prevent the instrument from reaching its intended depth.

The Perseverance impact experiment reinforces the same broader lesson:

Martian soil does not always behave the way simplified models predict.

One Small Correction Makes the Story Even More Interesting

The basic story of the Perseverance debris experiment is often summarized like this:

Two 77-kilogram tungsten weights and 539 kilograms of spacecraft debris hit Mars at 4.7 kilometers per second and created five craters.

That version captures the idea, but the real sequence is more precise.

The 4.753-kilometer-per-second figure refers to the spacecraft's velocity around the time the ballast masses were released, not necessarily their final surface speed.

A 2021 trajectory reconstruction estimated an impact velocity near 3.816 kilometers per second.

The 2026 study uses a probable value around 4 kilometers per second, while testing 5 kilometers per second because aerodynamic uncertainty leaves a broader possible range of 2.7 to 5.4 kilometers per second.

Likewise, the cruise stage itself had a mass of 539 kilograms.

The study does not say that one intact 539-kilogram block made three craters.

It says the stage fragmented, with fragments responsible for at least three resolved impact features.

Those details do not weaken the story.

They show why this was such an interesting physics problem.

Even when engineers know far more about an artificial impactor than they would know about a meteorite, atmospheric entry and fragmentation still create uncertainty.

The Most Important Discovery Was Not Simply That Mars Is "Soft"

It would be easy to reduce the finding to:

Mars has softer soil than scientists thought.

But that misses the deeper result.

The study did not demonstrate that every part of Mars has a cohesion of 7 kilopascals.

Mars contains dust, dunes, fractured rock, cemented crusts, sedimentary deposits, lava plains and many other materials.

The measurement applies to the weak near-surface target material associated with the candidate ballast impacts.

The larger lesson is methodological.

A widely used shortcut for estimating target strength produced a misleading answer because the collision existed outside the conditions where that shortcut works well.

Detailed three-dimensional shock physics gave a very different result.

That lesson can influence how scientists interpret other craters.

Five Holes in Mars Became a Physics Laboratory

The sequence is almost absurdly elegant.

NASA needed tungsten weights to balance a spacecraft.

Those weights became unnecessary during entry.

Engineers threw them away.

They fell through the Martian atmosphere.

They struck the ground at hypervelocity.

An orbiter photographed the holes.

Scientists knew what the projectiles were.

Years later, those holes became a laboratory.

From two craters only about 3.5 meters wide, researchers extracted information about the mechanical strength of Martian regolith.

From the mismatch between observation and theory, they discovered a limitation in conventional crater-scaling relationships.

And from pieces of hardware designed only to make a landing possible, they identified a potential new scientific strategy for future planetary exploration.

That may be the most remarkable part of the story.

Perseverance's discarded hardware did not merely crash.

It measured Mars.

Frequently Asked Questions

Did Perseverance create craters on Mars?

Yes. Researchers identified five fresh resolved craters associated with hardware discarded during the Mars 2020 mission's arrival. Two are considered the best candidates for impacts by tungsten cruise ballast masses, while three are attributed to fragments of the cruise stage.

How heavy were Perseverance's tungsten ballast weights?

Each Cruise Ballast Mass Device weighed about 77 to 77.5 kilograms and was made from tungsten.

Why did Perseverance carry tungsten ballast?

The weights helped configure the spacecraft's center of mass and aerodynamic lift during entry. They were released when they were no longer required for the landing sequence.

How fast did the tungsten blocks hit Mars?

An earlier NASA trajectory reconstruction estimated roughly 3.816 kilometers per second at impact. The 2026 crater study considers approximately 4 kilometers per second the most probable value and also models 5 kilometers per second to reflect aerodynamic uncertainty.

Did they hit Mars at 4.7 kilometers per second?

Approximately 4.753 kilometers per second was the spacecraft's speed around the time the ballast masses were released, while still more than 1,200 kilometers above the surface. Their reconstructed surface impact speed was lower.

At what angle did the ballast masses strike Mars?

Trajectory simulations indicate an extremely shallow impact angle of about 10 degrees from the horizontal.

Where are the artificial Perseverance craters?

They are roughly 70 kilometers northwest of the rim of Jezero crater, within terrain connected to the broader watershed surrounding Jezero.

How many craters were discovered?

Researchers identified five resolved new craters. Additional smaller markings may represent unresolved impacts from other spacecraft fragments.

How large are the craters?

The five measured craters range from about 2.6 to 6.3 meters in diameter. The two best candidates for the tungsten ballast impacts are each approximately 3.5 meters wide.

How did scientists prove that the craters were new?

Researchers compared orbital images taken before and after Perseverance's February 2021 arrival. The features were absent in earlier imagery and appeared afterward with fresh crater rims, ejecta and characteristic surface-brightness changes.

What did the impacts reveal about Martian soil?

Three-dimensional shock-physics modeling indicated a target cohesion of approximately 7 ± 1.5 kilopascals, consistent with relatively weak Martian regolith.

Why did conventional crater models give the wrong result?

The impacts combined an unusually dense tungsten projectile, much lower-density Martian soil and an extremely shallow impact angle. Under those conditions, the tungsten penetrated deeply and conventional scaling relationships did not reproduce the crater-forming physics accurately.

How wrong were the normal crater-scaling equations?

Using conventional scaling relationships implied effective strengths of approximately 50 to 200 kilopascals, whereas the more realistic 3D modeling produced about 7 kilopascals. The study concludes that the scaling approach can deviate by roughly an order of magnitude in this unusual impact regime.

Is the Martian surface really as soft as sand?

At the studied impact sites, the modeled cohesion is consistent with weak regolith rather than solid competent rock. However, Mars has many different surface materials, so the 7-kilopascal estimate should not be generalized to the entire planet.

How does this compare with NASA's InSight mission?

The InSight lander's self-hammering "mole" encountered an unexpectedly cohesive, low-friction duricrust that prevented it from digging properly. Previous analysis estimated cohesion values overlapping the range inferred from the Perseverance ballast craters.

Did InSight detect the Perseverance ballast impacts?

No identifiable seismic signal from the impacts was detected by InSight, which was approximately 3,450 kilometers away. The non-detection still allowed researchers to constrain how efficiently impact energy is converted into seismic waves on Mars.

Could future spacecraft intentionally create scientific craters?

Yes. The authors argue that future missions could deliberately use discarded ballast or other mission hardware as controlled impactors. If mass, material, trajectory and speed are well constrained, the resulting craters could be used to measure surface and shallow subsurface properties.

What study reported these findings?

The research was published in Geophysical Research Letters in September 2026 as "Probing Subsurface Properties With Mission Hardware: Lessons Learned From Artificial Impacts of Mars 2020," by A. J. Sokołowska, I. J. Daubar, G. S. Collins, F. Calef and A. Jones.