After investigating the high-standing bedrock at the Bunsen Peak workspace deep within the Margin Unit, the unique nature and composition of this rock was deemed worthy for collection of Perseverance’s 24th rock core sample, Comet Geyser!

Bunsen Peak is named after a prominent peak in Yellowstone National, Park, Wyoming, USA, and the namesake for Comet Geyser is the silica-sintered cone geyser also in Yellowstone National Park.

Although this rock’s origin remains under investigation and the rover team continues to explore different hypotheses, this core is particularly exciting because it appears to be composed primarily of two minerals: carbonate and silica. Carbonate and silica are both excellent minerals for preserving biosignatures (ancient signs of life). These minerals also have the potential to record the environmental conditions in which they formed, making them important minerals for understanding the habitability of Jezero crater billions of years ago.

The presence of carbonate within the Comet Geyser sample suggests that water, carbon dioxide, and chemical elements derived from rocks or sediments in and around ancient Jezero crater once reacted here to form carbonate. Carbonate minerals from Earth’s rock record are often used to reconstruct ancient climate--including conditions like temperature, precipitation, and aridity--and the history of life. Similarly, silica phases form when water interacts with rocks or sediments. The composition and crystallinity of silica can reveal the extent of the interaction with water, such as the intensity or duration of weathering and the pressure/temperature conditions during formation.

 On Earth, biosignatures can be preserved in carbonate and silica for millions of years, or even billions of years in the case of silica. Some of the oldest evidence we have of life on Earth is from rocks that contain fragments of microbial cells that were “permineralized” by silica, a fossilization process that entombs the residues of ancient life and protects them from degradation. Thus, rocks containing these materials are considered among the highest priority samples for investigating whether Jezero crater was once host to microbial life. Perseverance’s 24th core sample at Bunsen Peak represents a significant milestone towards collection of a scientifically diverse set of samples for eventual return to Earth as part of the Mars Sample Return mission.

With rock core #24 now onboard, Perseverance presses forward towards its next strategic objective of investigating a location called Bright Angel, which is a light-toned outcrop exposed in the ancient channel wall of Neretva Vallis. Challenges may arise on this journey, as the terrain ahead is littered with sharp boulders and sand that are proving difficult for the rover’s auto-navigation system. The mission’s rover planners are working hard to manually navigate this tricky terrain. In the meantime, the science team is eagerly anticipating the secrets the rocks of Bright Angel may hold!

Written by
Adrian Broz
Postdoctoral Scientist at Purdue University/University of Oregon

Nowhere on Earth can we fully replicate the conditions on Mars. Special facilities can re-create certain elements with enough fidelity to test specific scenarios, but each is limited, leading to a plethora of platforms and scenarios required to span the conditions of Mars. In our prior post, “The Right Stuff,” the focus was using Ingenuity on Mars to test our macro capabilities: flying higher and faster, landing at various speeds, and generally expanding the flight envelope to retire the associated risk for future Martian rotorcraft. The holy grail, however, is understanding the microscale – not just proving Ingenuity can fly faster but knowing how it flies faster.

To answer the question, the NASA JPL Ingenuity team worked with our aerodynamics partners at NASA Ames to design, validate, and execute a Sys-ID test campaign. “Sys-ID” refers to a process called system identification, a data-driven method for understanding the complex behavior of a system by studying how specific inputs impact the motion of the vehicle.

In this case, a frequency sweep (sine wave with varying frequency) was injected into the control input to cause microscopic “nodding” of the vehicle in forward flight. The aerospace industry has long relied on these methods to characterize complex vehicle dynamics and validate simulation models. The same methods were used during ground testing of Ingenuity on Earth, but as previously noted, there was no comprehensive test environment on Earth to conduct full system testing like traditional Earth rotorcraft endure.

During the early phases of the mission, the required dynamic maneuvers were viewed as too risky to perform in-flight on Mars. As Ingenuity entered its third year of operations and neared the end of its ability to expand the flight envelope, the risks of Sys-ID became smaller and easier to justify. In late 2023, a three-month effort was spent to develop, test, and uplink a new software version that connected portions of Ingenuity’s software that were used for Earth-based Sys-ID testing with the code that controls the vehicle when flying horizontally.

Animation depicts control input that results in microscopic “nodding” of the vehicle in forward flight.

The opportunity to conduct a Sys-ID flight was found in December 2023. Conditions were ideal within the lower section of Neretva Vallis (believed to be an old river valley) due to the terrain being nearly as flat as on the crater floor. Additionally, the mission schedule allowed for a break from the regular flights needed to stay ahead of the rover as it was conducting a scientific loop through Gnaraloo Bay. Two dedicated flights (Flights 68 and 69) were executed that successfully demonstrated the Sys-ID method in-flight and, for the first time on another planet, characterized the vehicle’s flight dynamics.

These flights prioritized collecting data in high-speed forward flight conditions – both within and beyond Earth-based testing to correlate and extend our knowledge. The importance of this is highlighted by Allen Ruan, Ames aeromechanics flight dynamicist, “Getting the data from these two flights, especially at the high forward flight speeds, closes the loop on prior years of simulation and ground testing and informs us on improvements for dynamics modeling and estimation of future Martian rotorcraft.”

The reason that these flights are so significant is because they provide key fundamental validation of rotorcraft models and methods which would otherwise require conditions that are impossible to replicate here on Earth. As explained by Tove Aagren, lead simulator at Ames and designer of the Sys-ID campaign, “An inherent challenge of working with Mars rotorcraft is that of model validation. Extraterrestrial flight necessitates high confidence in our prediction models, yet replicating the true flight condition to gain this confidence across an entire flight envelope in Earth-based testing is highly non-trivial. To this day, aspects of forward flight dynamics of Ingenuity remain associated with uncertainty. This is what makes the opportunity to characterize key vehicle dynamics in the true operating condition, i.e. on Mars, incredibly exciting. Not only for the novelty of the approach, but for the fundamental insights that we really cannot gain in any other way than through designated system identification flights.”

In order to execute this type of maneuver, Ingenuity had to fly a record distance at the previously tested max groundspeed of 10 m/s (22.3 mph). An out-and-back flight with Sys-ID segments in each leg guaranteed that for an expected east-west wind direction at least one leg is into the wind enabling testing at an airspeed greater than 10 m/s. Getting two flights’ worth of data at these high speeds provides a treasure trove that allows the team to increase confidence in the behavior of future rotorcraft at Mars.

Additionally, now that these Sys-ID methods have been demonstrated successfully, a process has been established that can be replicated for characterizing future flight vehicles earlier in their mission. This would better define the vehicle’s performance, allowing the operations team to plan with fewer unknowns and could enable future rotorcraft to be tested on Earth to meet only the minimum capability needed to complete the mission, and then validated to higher levels of performance after landing.

With in-flight system identification complete, Ingenuity followed in the footsteps of countless legends, test pilots who first pushed the limits of aerial flight, then space flight, and now Martian flight.

Martin Cacan, Chief Pilot for Ingenuity Mars Helicopter at NASA’s Jet Propulsion Laboratory, and Shannah Withrow-Maser, Rotorcraft Aeromechanics Lead at NASA’s Ames Research Center

Studying the atmosphere with Perseverance can be challenging! Imagine spotting an interesting cloud in a photo taken yesterday; unlike something interesting on the surface, more observations just aren’t possible, as it’s long gone by now. Or imagine trying to take a movie of a dust devil zooming across Jezero crater, when the rover’s daily activities are all planned out before the rover even wakes up. The fact that many atmospheric phenomena are short-lived and/or hard to predict, and often only occur during certain time periods, means that atmospheric scientists on the Mars 2020 team must use different strategies to observe them.

Firstly, the sensors that make up the primary atmospheric instrument (the Mars Environmental Dynamics Analyzer, MEDA) make meteorological and related observations continuously at least every other hour of every sol. This gives us a very good chance of capturing transient and hard-to-predict phenomena.

Secondly, for sensors that can’t measure as often - like the cameras and microphone - we take measurements over multiple sols at different times and (for imaging) directions, to build up statistics on when and where interesting phenomena occur.

Thirdly, when we expect to see something unusual based on the time of year or location, we increase the cadence of measurements to make sure we capture that event. In Perseverance’s first year on Mars we observed a scattering halo toward the end of Mars’s cloudy season. This bright ring around the Sun is caused by large hexagonal ice crystals that only form when lots of water vapor is present. Despite dozens of attempts to image another in the second Mars year, it wasn’t until our last attempt - right before the cloudy season ended - that we saw one (see figure)!

And finally, when a longer-lived rare event is underway, we react by adding in more measurements. There are currently lots of dust storms happening on Mars, and with some passing right over Jezero we’ve recently measured the largest dust opacities of the entire mission to date! So we’ve been taking additional observations to tell us about how the atmospheric state, dustiness, and local dust lifting have been changing due to this storm activity.

For many of these observations, we don’t know if we’ll even ‘catch’ the atmospheric phenomena we’re trying to study until we get the results back on Earth. But even knowing when, where, and under what conditions something doesn’t occur is very useful. And by persevering, we’ve been able to obtain fantastic observations of everything from clouds and halos to dust devils and the onset of dust storms.

Written by Claire Newman, Atmospheric Scientist at Aeolis Research

Back in 2022, Perseverance found my favourite rock on the mission so far: a flat piece with a mushroom-shaped rock feature sticking out of it! The “mushroom” is about 1-2 cm tall and less than 1 cm wide. The rock was in an area the rover explored called Hogwallow Flats. Many aspects of Hogwallow Flats set it apart from the rest of the rocks in Jezero: it was very fine-grained compared to other units, it contained a higher proportion of sulfate salts, and it had interesting rock features like the “mushroom” within it.

The “mushroom” is actually a geologic feature known as a concretion. Concretions are solid masses within a rock that form as water flows through sediment, dissolving minerals and reprecipitating them in a more compacted configuration. Concretions are usually harder than the surrounding rock, making them less vulnerable to erosion and weathering. On Earth, concretions come in a wide variety of shapes (spherical to irregular) and sizes (1 mm to 2.2 meters) and they first appear in the terrestrial rock record over 3 billion years ago. We do not know when the “mushroom” concretion at Hogwallow Flats was first formed but as wind carved out the surface of Mars over billions of years, it eroded the softer bedrock around this hard concretion. Now all that’s left of the surrounding bedrock is a very thin rock spire connecting the concretion to the flat rock below, like a miniature version of the giant hoodoo features of the American southwest. Near this interesting feature, we also saw big, disc-shaped concretions, small, spherical concretions, and pointy concretions! It was an exciting summer, full of a variety of concretion shapes. The rover cored a sample from Hogwallow Flats called ‘Bearwallow’ that may contain a concretion so if the samples are returned to Earth, we will be able to learn even more about martian concretions and how they were formed! Another interestingly wind carved martian rock is this ‘spoon’ shaped rock captured by Curiosity rover in 2015.

Written by
Hemani Kalucha
Ph.D. Student at Caltech

Perseverance has continued its traverse west through the Margin unit. As the rover drives, images and data are obtained using instruments such as Mastcam-Z, Navcam, and SuperCam to track any changes in the chemistry or appearance of the rocks.

Along the way, the science team used these images to pick out an exciting rock named Bunsen Peak. This rock was intriguing because it stands tall among the surrounding terrain and has some interesting surface texture on its left face, as seen in the image above. Another feature of the rock that stood out in the image was the near vertical face directly in front of the rover. A vertical face piques the interest of the science team for a couple of reasons: first, a vertical face of a rock could give a cross-sectional view of any chemical or physical layering that might be occurring in the rock. Second, a vertical face is usually less dust-covered, which is good news for our scientific instruments!

Dust coatings on a rock surface can obscure the actual chemistry of the rock underneath, so it is important to look for less dusty surfaces for obtaining data and pictures. For example, in the Bunsen Peak rock, you can see where there are curved or angled surfaces of the rock that are lighter in color due to dust accumulation. Other surfaces, however, such as the protruding lip of rock the rover’s arm is investigating, are more vertical and appear darker, indicating less dust cover and a better spot for the rover to explore. We chose that spot to probe the chemistry of Bunsen Peak.

Captured in action is the WATSON (Wide Angle Topographic Sensor for Operations and eNgineering) camera, which takes close-up, high-resolution pictures of the rock’s surface. The SuperCam LIBS (Laser-Induced Breakdown Spectroscopy) instrument also performed chemical analyses on Bunsen Peak that can be correlated to the high-resolution images of WATSON to provide a well-rounded view of the texture and chemistry.

The rover will continue its trek west, using its instruments to monitor for any more rocks that will complete the story of the Margin unit campaign.

Written by Eleanor Moreland, Ph.D. Student at Rice University

There has been much discussion and interest regarding the origin of the Margin unit. The Margin unit has gained interest due to the presence of carbonates and its implications for the paleoenvironment and biosignature preservation of ancient Mars. There are several possible origins for the Margin unit, and further analysis of these rocks will shed light on what environment the Margin unit formed in during Mars' ancient past. Examining the carbonate may also help us understand the processes that occurred after the Margin unit was deposited.

As Perseverance heads west through the Margin unit, there has been more interest in abrading these rocks to determine whether the Margin unit is different from the previous two samples-- Pelican Point and Lefroy Bay--collected from the Margin unit at the Hans Amundsen Memorial Workspace and Turquoise Bay, respectively. Abrasion and proximity science will also provide useful geochemical and textural information that can be used to infer information about the depositional and post-depositional conditions.

Upon returning to Earth, additional laboratory analyses, such as fluid inclusion analyses, clumped isotope thermometry, and classic stable isotope analysis, can determine the temperature, pH, and salinity of the water in which these carbonates were formed. These types of analyses are frequently performed on terrestrial samples on Earth to better understand the climate on Earth during the ancient past when humans did not have instruments or historical records. We may be able to use certain characteristics of the carbonate in the margin samples as “climate proxies” to tell us about the specific environmental conditions of ancient Mars. Additionally, if the Margin unit contains radiogenically datable material, then a sample from this region could be used to constrain the timing of the unit’s formation and its relationship to the Jezero crater paleolake.

Nicolas Randazzo, Postdoctoral Scientist, University of Alberta

Perseverance continues its uphill march through the tricky terrain of the margin unit, an area with enhanced signals of carbonate. We are headed toward a region we’ve nicknamed “Beehive Geyser,” an area about 500 m to the west. What draws us here? Well, this region lies approximately 60 m above the part of the margin unit that we encountered and sampled for the first time last September. By comparing the rock’s characteristics at this higher interval with what we’ve already seen, we hope to uncover clues about the emplacement and history of the unit.

In recent days, the team has been excited by data from the rover’s RIMFAX instrument, which uses radar waves to map out subsurface layers underneath the rover. Several days ago, the rover passed across a ridge that appears to correspond to one of these subsurface layers. Intrigued, we’ve spotted a large rock in the ridge’s vicinity we’ve nicknamed “Bunsen Peak”. Later this week, we plan to drive up to this rock and attempt proximity science using the rover’s arm. In the meantime, we’re acquiring images of the nearby ridge, as well as chemical data on nearby rocks and sand using the SuperCam laser.

Once we’ve completed our excursion to “Bunsen Peak”, we’ll resume our journey towards “Beehive Geyser.” The science team is eager to gather more observations that will help us to uncover the secrets of the mysterious margin unit!

Written by Athanasios Klidaras, Ph.D. Student at Purdue University

After 72 flights and 17 kilometers flown, it is finally time for us to say goodbye to the Ingenuity helicopter. It was announced last week that Ingenuity’s mission is now coming to an end after it sustained damage to a rotor blade on its final flight. Ingenuity’s long and remarkably successful journey began three years ago on the floor of Jezero Crater and it will end in Neretva Vallis, a channel that once brought water into an ancient lake. Ingenuity became the first craft to achieve controlled and powered flight on another planet, giving the science team access to landscapes inaccessible to any rover. This week Perseverance drove within ~450 meters of the helicopter, which is likely the closest we will be to our flying companion for the remainder of our mission. We took this opportunity to acquire long distance imagery of Ingenuity with our Mastcam-Z instrument.

While Ingenuity’s mission has reached its conclusion, Perseverance is approaching one of the most exciting parts of its mission so far. Perseverance is continuing to explore the margin unit, an area on the edge of Jezero Crater with strong signatures of carbonate minerals from orbit. Our team made the most of this latest stretch of terrain, taking SuperCam LIBS and VISIR observations of a pitted rock named Porkchop Geyser and capturing Mastcam-Z images of a rubbly outcrop called Muiron Island. As the rover makes its way west, we are diligently preparing for what lies ahead. In orbital imagery of the crater rim we can see huge blocks – so called 'megabreccia' – which are hypothesized to originate from the impact that created Jezero Crater or represent even older rocks ejected from the massive Isidis Basin to our east.

While it is sad to be leaving Ingenuity behind, the future is bright for Perseverance and the science team is in high spirits. Ahead of us lies the mysterious crater rim, which may offer a window into a period of Mars’ history that no rover has ever seen before.

Henry Manelski, PhD Student at Purdue University and Nathan Williams, Science Systems Engineer at JPL

Perseverance is deep within the ongoing Margin Unit campaign, where orbital signatures of carbonate minerals appear strongest. After collection of a drilled rock core from the Margin Unit, followed by 20 Sols (Martian days) parked at our current workspace, Perseverance had ample time to explore the rocks adjacent to the rover and perform long distance multispectral imaging of the Jezero Crater Rim with the Mastcam-Z instrument.

The science team has been working around the clock to understand the origin, composition and alteration history of massive, dark-toned rocks in the Margin Unit. Challenges abound, however, as many of these exposed rocks are covered in a thick, crusty dust layer that partially obscures our ability to understand their true composition.

Perseverance is approaching a small, ~50-m-wide impact crater that has created a natural cross-section of rock layers of the Margin unit, potentially providing new views of deeper bedrock. The team is eagerly awaiting images of the interior of this small crater, which could reveal information about the emplacement of the upper Margin Unit.

In the upcoming rover traverse, Perseverance will climb up onto the Jezero Crater Rim after a stop in Neretva Vallis, a deep channel that appears to have once fed water and sediments into Jezero Crater. The first long-distance glimpse of this uncharted territory did not disappoint!

Based on orbital satellite images, rock layers near the Jezero Crater Rim are thought to be among the oldest rocks that could be explored by a rover on Mars. Therefore, the light-toned rock layers pictured here could represent much older strata than has yet been explored by Perseverance – possibly dating back to the Noachian (approximately 3.7 – 4.1 billion years ago). Exploration of these terrains could provide unprecedented insight into the climate and environmental habitability during earlier and possibly wetter periods in Mars’ history.

In anticipation of Perseverance’s upcoming Crater Rim traverse, the team has been working to use orbital images to create a high-resolution map of geological features throughout the Crater Rim, including the light-toned bedrock in the image. These geological maps will be used to plan the upcoming traverse of the Crater Rim and for outlining the highest-priority rock units for collection of drilled rock core samples that could one day be returned to Earth.

Written by
Adrian Broz
Postdoctoral Scientist at Purdue University/University of Oregon

Since parking at Airey Hill during Solar Conjunction back in November, Perseverance has been busy exploring. We drove north from Airey Hill to Flat Point, where we had the best views to conduct imaging using Mastcam-Z of some of the deepest parts of the Margin Unit. We then drove south-east, parallel to a ridge that shows apparent layering, and imaged targets including Burnt Island and Lily Bay. It was then time to wrap up our excursion into the area known as Gnaraloo Bay, pass through Jurabi Point once more, and continue east across the Margin Unit. Our next goal is to reach an area called Beehive Geyser, which is on the eastern side of the Margin Unit and adjacent to the Neretva Vallis channel. If you want to keep up to date with where Perseverance is driving, you can see the rover’s traverse and current location on this interactive map.

The Mars 2020 science and operations team, as well as Perseverance itself, took some well-earned downtime over the December holiday period, but operations resumed in early January. The Margin Unit has proved tricky terrain for driving, so drive progress has been slow going, but Perseverance continues to (you guessed it!) persevere. We conducted proximity science on a dust-cleared natural surface bedrock target named Minga using PIXL, SHERLOC and WATSON (Minga is seen in the above Mastcam-Z image). Unfortunately, a SHERLOC issue during these proximity science activities left the arm unstowed and prevented us from driving away. The team has since stowed the arm, Mars 2020 engineers have been working to diagnose the issue, and the rover has resumed driving.

As always, we made the most of the bonus time at our last location to gather a treasure trove of scientific observations. These include Mastcam-Z multispectral imaging of targets Browera and Naronga, which show a delightful diversity of minerals at the grain level that pop up as a kaleidoscope of color in our multispectral data products; SCAM LIBS and VISIR observations on potential veins at targets Yardie Creek and Ayliff; and SCAM LIBS and VISIR and Mastcam-Z multispectral imaging of target Quailing which shows an interesting pitted texture.

There’s never a dull day on Mars, and we’re looking forward to lots of new observations in 2024!

Written by Eleni Ravanis, Student Collaborator at University of Hawaiʻi at Mānoa

On Saturday, Jan. 20, communications were reestablished between Ingenuity and NASA’s Perseverance rover. The Ingenuity team has determined the helicopter is power-positive and is sitting vertically on the surface. Next steps include running further diagnostic checks, commanding Ingenuity to take photos of its location on the surface, and performing a spin test. 

On Jan. 18, NASA’s Ingenuity Mars Helicopter executed its 72nd flight at the Red Planet. The flight was designed as a quick pop-up vertical flight to check out the helicopter’s systems, following an unplanned early landing during its previous flight. Data Ingenuity sent to the Perseverance rover (which acts as a relay between the helicopter and Earth) during the flight indicates it successfully climbed to its assigned maximum altitude of 40 feet (12 meters). During its planned descent, communications between the helicopter and rover terminated early, prior to touchdown. The Ingenuity team is analyzing available data and considering next steps to reestablish communications with the helicopter.

• Flight 72
• Expected flight date: 01/18/2024
• Horizontal flight distance: 0 meters
• Expected flight time: 32.08 seconds
• Flight altitude: 12 meters
• Heading: NA
• Max flight speed: 0 m/s
• Goal of flight: Pop-up Flight - Localization
• Airfield: Same

• Flight 71
• Expected flight date: 01/06/2024
• Horizontal flight distance: 358.3 meters
• Expected flight time: 124.92 seconds
• Flight altitude: 12 meters
• Heading: West
• Max flight speed: 7 m/s
• Goal of flight: Reposition Helicopter
• Airfield: Same

• Flight 70
• Expected flight date: 12/22/2023
• Horizontal flight distance: 258.735 meters
• Expected flight time: 129.37 seconds
• Flight altitude: 12 meters
• Heading: West
• Max flight speed: 3 m/s
• Goal of flight: Reposition Helicopter
• Airfield: Same

Trailblazer

Long before Ingenuity’s historic first flight on Mars, engineers at NASA’s Jet Propulsion Laboratory in Southern California and their collaborators at AeroVironment Inc. were already moving the boundaries of human knowledge and aeronautic achievement with testing here on Earth. Flights by an Ingenuity prototype in 2016 showed that controlled, aerodynamic flight was possible in a Mars-like atmosphere for the first time. These flights were made possible by JPL’s 25-foot thermal-vacuum chamber, which is capable of replicating environments with a wide variety of temperatures, pressures, and compositions. Despite being one of the largest thermal-vac chambers in the world, it was still too small for significant horizontal motion, mostly limiting test flights to simple hovering. Engineers worked around this to some extent by building a custom wind wall to simulate Martian winds and the aerodynamic conditions seen in forward flight. Here, too, there were limits in how much and how well the conditions of Mars could be tested. Ultimately, the helicopter still had much to prove when it spun up its rotors for its first real flight test on the planet for which it was designed. This historic first flight on April 19, 2021, was performed flawlessly, matching its performance in countless chamber tests almost exactly.

That first, modest 3-meter (9-foot) hover flight, though impressive, was still quite far from testing Ingenuity’s limits. Over the next six months, the Ingenuity team methodically probed the helicopter’s abilities, pushing it just a little harder with each flight. Altitude was increased to 5 meters on Flight 2, and then 10 meters on Flight 5. Forward flight was attempted for the first time on Flight 2 at a cautious 0.5 m/s. By Flight 10, Ingenuity was flying at an altitude of 12 meters (40 feet) and a speed of 5 meters per second (11 mph), showing just how far engineers from NASA and AeroVironment had pushed her since those early chamber tests half a decade earlier.

These early-mission records would remain largely in place for the next year as the Ingenuity team transitioned the vehicle from a simple technology demonstrator (akin to the first Wright brother’s airplane) to a functional science and scouting asset on the surface of Mars. Learning how to coordinate the activities of the rover and the helicopter to take advantage of Ingenuity’s unique capabilities (and limitations) took time and effort. To understand the audacity of the attempt, one might imagine how difficult it would have been to attempt to provide regular commercial passenger service with the Wright Flyer in 1903.

Reaching the limits

By early 2023, Ingenuity found itself literally racing for its life up the Jezero river delta, and the limits imposed by these early-mission speed/altitude records made it difficult to stay ahead of the rover in the narrow channels of the Jezero delta. To understand the mission impacts of Ingenuity’s flight envelope, it’s necessary to discuss the general set of constraints that shape the process of flight planning for Ingenuity.

1. Energy – Flights draw enormous amounts of energy from the onboard battery in a short period of time. As the battery is discharged during a flight, its ability to support these high power levels also decreases. Below a certain level, the battery won’t be able to meet the power needs of the helicopter, leading to destabilization or a system-wide brownout, both of which would result in a crash.
    
2. Heat – Flights generate significant heat in various components of the helicopter. If flights continue for long periods of time, components could begin to overheat and fail, resulting in a crash. The time when this would occur depends on the components’ starting temperature, the environment in which they’re operating, and the exact composition of the flight.
    
3. Terrain – Martian terrain directly impacts navigation performance, and highly variable terrain can cause control effort spikes which also create power spikes that the battery needs to support. In addition, sufficiently rock-free airfields define the set of paths available to the helicopter.
    
4. Safety and Landing Accuracy – The constraints and capabilities highlighted above can drive Ingenuity far off course, even if not severely enough to interrupt the flight. This could result in the helicopter landing in an unsafe location, resulting in a crash. All flights must be studied in advance to ensure vehicle safety during the flight and at landing.

The common denominator in all these constraints is time. Saving flight time saves energy, reduces heating, and provides more freedom to use slower speeds to tiptoe around disruptive terrain that might otherwise endanger or significantly degrade the landing accuracy of the helicopter. Higher speeds and higher accelerations reduce the time needed to execute a given flight path. Higher altitudes permit higher speeds, as the wider field of view helps to keep ground features in view of Ingenuity’s navigation camera longer, counteracting the effect of increased speed. Expanding Ingenuity’s flight envelope had the potential to relax flight planning constraints and allow Ingenuity to operate more effectively alongside Perseverance. The team resolved to change focus, actively looking for opportunities to resume testing and expand the flight envelope. Ingenuity would once again return to the business of pushing the boundaries of Martian flight and setting countless flight records along the way.

A Return to Form

This new approach started paying dividends on Flight 45, where new records for both speed and acceleration were set. Maximum flight speed was increased to 6 m/s and horizontal acceleration was increased from the previous maximum of 0.75 m/s2 (first used in Flight 25’s record-setting run across Seitah) to a new, more aggressive 0.85 m/s2. Shortly afterwards, during Flight 49, the maximum speed was increased to 6.5 m/s with a hover of 16 meters at the end of the flight. The maximum altitude ceiling was pushed out again just 10 days later during Flight 50 with a 2-meter increase to 18 meters.

Still, such work was difficult to do while maintaining Ingenuity’s normal operational schedule. Significant effort is needed to keep Ingenuity flights synchronized with the rover’s movements over difficult terrain while staying in communications range. Finally, as Perseverance approached the Mandu Wall region in September of 2023, the Ingenuity team saw the opportunity we needed. The relatively permissive communications environment and flat terrain around Jurabi Point offered the perfect environment to perform the type of testing that the lower Jezero delta regions had made so difficult.

Somewhat ironically, for all the focus on flying faster, one of the highest-priority tests involved reducing the vertical landing speed below the standard 1 m/s descent rate. This capability was a priority for the next planned Martian helicopter, the Sample Recovery Helicopter (SRH), which is being designed to retrieve the sample tubes dropped by Perseverance. The initial design of SRH uses Ingenuity as a starting point but carries extra mass in the form of a robotic arm and wheels needed to enable sample retrieval along with the sample tube itself. These additions increase the predicted stress on the landing gear during touchdown. A softer landing would be easier on the landing gear but harder for the touchdown detection algorithm to identify, and, at the extremes, can result in multi-contact events that could cause a crash. On Earth, landing at Mars gravity levels is difficult to test in a realistic manner and must instead be partially tested across multiple venues. Fortunately, we already have a flying vehicle on Mars and the team could use Ingenuity as a testbed, collecting real world data on landing speeds needed by the SRH project. After careful study and re-tuning parameters around a 0.75 m/s descent speed, Flights 57-59 demonstrated the soft touchdown on both flat and sloped terrain.

Flight 59 also served the purpose of increasing the maximum altitude at hover to 20 meters, allowing forward flight up to 16 meters. Typically, 4 to 6 meters of altitude ceiling are held in reserve to account for slant range when tilted and for variable terrain and the resulting control system response. This enabled Flight 60 to set a new maximum speed record of 8 m/s as the helicopter flew to Jurabi Point. Flight 61 was a near-repeat of 59 that further expanded the flight regime. The ascent speed was increased to 1.5 m/s and descent speed to 1.2 m/s, both previously just 1 m/s, saving around 10 seconds on the typical flight. The flight also achieved the highest altitude to date at 24 meters. This was a large milestone as it surpassed the analytical worst-case drop-out of the laser range finder (LRF) which is used to measure Ingenuity’s altitude above ground level. If the LRF drop-out extends longer than 2 seconds, the helicopter will fault and land (likely safe in the case of a hover flight, but possibly fatal during forward flight). This altitude also enabled the team’s goal of forward flight at 10 m/s demonstrated in Flight 62 at an altitude of 18 meters in forward flight. Of course, Ingenuity hadn’t forgotten its partner on the Red Planet. In the middle of this record-setting flight, Ingenuity managed to capture several high-resolution photos of the Jurabi Point region many sols ahead of the rover’s arrival.

In summary, this flight test campaign has been a tremendous success, proving that our intrepid rotorcraft is still capable of breaking records and pushing the envelope 2 ½ years after landing on Mars. Over the last 9 months, the Ingenuity team has doubled our maximum flight altitude limit from 12 to 24 meters, nearly doubled our max speed from 5.5 m/s to 10 m/s, increased our maximum horizontal and vertical acceleration, and validated both soft- and hard-landing approaches. Despite this rapid pace, the team isn’t slowing down. We intend to keep pushing to see what new things can be learned and what new capabilities can be mastered with our small helicopter on the Red Planet.

Travis Brown, Chief Engineer, and Martin Cacan, Chief Pilot, Ingenuity Mars Helicopter at NASA’s Jet Propulsion Laboratory

In the vast expanse where dreams take flight,
A tale unfolds of courage and might.
Mars, the distant red planet's embrace,
Witnesses a duo, bound by space.

In the history of the cosmos, their story engraved,
Perseverance and Ingenuity, bold and brave.
Their legacy echoes, inspiring the souls,
To reach for the stars, to achieve their goals.

Perseverance, a wanderer on alien soil,
Unraveling mysteries, with unyielding toil.
Its robotic arm, a gentle touch bestowed,
Collecting samples, where the martian past’s secrets flowed.

But lo, a companion, the aerial acrobat of the skies,
Above rusty landscapes, it defied the ties.
A helicopter, a pioneer's grace,
Defying gravity, in an extraterrestrial space.

Across the crimson dunes, they fly and rove,
Martian exploration, endlessly strove.
Earth watched in wonder, hearts filled with pride,
As these brave emissaries explore Jezero and beyond far and wide.

Together they push boundaries, hand in hand,
Humanity's spirit, echoing across the sand.
For in their union, a message resounds clear,
That dreams and determination can conquer all fear.

Their mission began at the Octavia E. Butler Landing Site.
Wright Brothers Field where Ingenuity first took flight.
Séítah, Máaz, Tenby, Mandu Wall and others explored,
Collecting samples, ten cached at Three Forks, the rest remain aboard.

Everyday they dance, a cosmic ballet,
Mars2020's legacy, in a celestial display.
Ingenuity's blades whisper secrets unknown,
As Perseverance roams, etching paths above the stone.

Their tireless endeavors, a testament true,
To the boundless potential, within me and you.
For as we gaze upon the butterscotch skies above,
We're reminded of resilience, courage, and love.

So let the spirit of Perseverance forever thrive,
In the hearts of dreamers, who dare to strive.
And may Ingenuity's wings inspire us to be,
Explorers of the unknown, seekers of destiny.

For in the grand tapestry of the cosmos above,
Mars2020's legacy, a testament of our love.
To unravel the universe, one discovery at a time,
Together we'll soar, with passion so sublime.

Nicolas Randazzo, Postdoctoral Scientist, University of Alberta

• Flight 69
• Expected flight date: 12/19/2023
• Horizontal flight distance: 702.37 meters
• Expected flight time: 131.10 seconds
• Flight altitude: 16 meters
• Heading: East-northeast
• Max flight speed: 10 m/s
• Goal of flight: Flight Test
• Airfield: Same

• Flight 68
• Expected flight date: 12/09/2023
• Horizontal flight distance: 828 meters
• Expected flight time: 146.56 seconds
• Flight altitude: 16 meters
• Heading: Northeast (out & back flight)
• Max flight speed: 10 m/s
• Goal of flight: Flight Test
• Airfield: Same

• Flight 67
• Expected flight date: 12/02/2023
• Horizontal flight distance: 392.84 meters
• Expected flight time: 133.57 seconds
• Flight altitude: 12 meters
• Heading: Northwest
• Max flight speed: 5.3 m/s
• Goal of flight: Reposition the helicopter
• Airfield: New

Astrobiology is the study of the origin, evolution, and distribution of life in the Universe, and searching for life on Mars is a major goal of the Mars 2020 mission. While humans have long wondered whether there are others like us, it’s only been a few decades since we’ve developed the technologies to search for life beyond Earth in earnest. With space-based telescopes like James Webb, astronomers look up for planetary-scale chemical signs of life on exoplanets; with ground-based radio astronomy, astrophysicists listen for signals or communications transmitted by intelligent species from galaxies faraway; and with landed missions to Mars and other Solar System bodies, planetary scientists and geologists look down for physical and chemical signs of life preserved in rock and ice. Finding extraterrestrial life is a central aspect of astrobiology, but finding no life on a once-habitably rocky planet like Mars would be equally important, because it would help us look back into our own origins to query what makes Earth biologically unique, and would also help us prepare to search for life elsewhere.

Jezero Crater was selected as the Mars 2020 landing site because of its astrobiological potential. Billions of years ago it hosted a lake, back when Mars was warm and wet, more hospitable and Earth-like. Water is essential for life as we know it, and sedimentary rocks that form through aqueous activity can be excellent physical preservers of biological materials. Perseverance has also found evidence for igneous minerals, and these lithologies can be important for life as well: on Earth, volcanic rocks provide energy-rich substrates for microbes to feed upon and inhabit. If ancient life existed in or around Jezero, fossilized remnants of those ancient organisms could still remain as morphological, elemental, or molecular biosignatures preserved in rock today. To aid in this search, Perseverance carries a suite of on-board instruments to select astrobiologically-interesting samples to send back to Earth. 23 cores have been collected thus far! Robotic rover tools can reveal a lot about potential for habitability, but returning physical samples is absolutely critical for determining whether these rocks do contain evidence of life. For example, billion-year-old cells and fossilized biomolecules preserved in geologic samples on Earth are studied with large, complex analytical instruments housed in laboratories. Returning cores from Jezero will allow scientists to apply the same techniques to extraterrestrial samples too! Regardless of what we find, searching for life in these little Martian rocks represents an astronomical leap towards determining whether there was life on Mars, which will in turn give us a better understanding of who we are, where we came from, and where we’re going.

Written by Denise K. Buckner, Student Collaborator at University of Florida

The Science Team directed Perseverance to Airey Hill, the parking spot chosen for Solar Conjunction. Although there will be a pause on data during conjunction, team members still analyze all the images taken on the drive before Perseverance parked and data delivery was paused.

While all returned images and data are exciting, these post-drive images showed an interesting rock that stood out to the Mastcam-Z (ZCAM) team. Pictured above, the rock Barrabiddy had interesting textures, such as the wind-abraded smooth rock faces, that caught the attention of team members. What adds to the intrigue is this rock seems to be part of an exposed outcrop that is in contact with the underlying bedrock. The initial ZCAM images suggesting a depositional contact inspired focused compositional analyses by the SuperCam instruments.

While these ZCAM images prompted observations on the Science Team, Barrabiddy also captured the eyes of the public. The above image of Barrabiddy was voted as Image of the Week for Week 142, receiving over 280 “likes” on Perseverance’s Raw Images page! Most images receive few likes, so the public’s interest in Barrabiddy is quite evident through their interaction. As a scientist and team member involved with communicating Perseverance’s science to the public, I always try to be aware of how to engage people and effectively share information about the rover. Seeing the images and data that excite the public is one way we, as scientists, can best engage others and bring everyone into the amazing journey of Perseverance.

While Perseverance is parked for solar conjunction, it is a great time to reflect on the journey so far. If you become restless during conjunction and want to look back at beautiful data from Mars, check out the past raw Images of the Week or the Mastcam-Z team-favorite images. Are you drawn to interesting rocks like Barrabiddy? Check out past blogs about other cool rocks Perseverance has imaged, like the rock shaped like a sombrero, a dragon’s egg, or ones with hidden illusions. Happy Solar Conjunction!

Written by Eleanor Moreland, Ph.D. Student at Rice University

Perseverance wrapped up science activities this week as the team focused on getting the rover in position for solar conjunction, a few week period roughly every two Earth years when Earth and Mars are on opposite sides of the Sun. To avoid potential interference of radio signals by the Sun’s ionized gas, engineers do not actively command Mars spacecraft during this period and rather send up a long list of commands prior that don’t require input from the team and keep the spacecraft busy. This year’s solar conjunction will last from Sols 967 to 987 (Nov. 8th-28th, 2023). This is Perseverance’s second solar conjunction of the mission, the last one occurring in October 2021 when we were exploring the crater floor at South Séítah. 

After a slow-going but successful traverse north through a difficult boulder-rich terrain, Perseverance arrived at Jurabi Point on Sol 958 (Oct. 31st, 2023). The team took advantage of the view to do some pre-drive imaging of nearby boulders and reconnaissance for our traverse ahead before dropping down into Gnaraloo Bay with a 301 meter drive eastward on Sol 959 (Nov. 1st, 2023). Gnaraloo Bay is a geologically intriguing location with three different units outcropping in close proximity, including a boulder-rich upper fan unit, the margin unit, and curvilinear strata potentially consistent with rocks previously investigated by Perseverance. On Earth, field geologists seek out such boundaries, or 'geologic contacts,' to constrain stratigraphic relationships and depositional histories of the different rocks and the team hopes to do the same at Gnaraloo Bay.

A 42 meter slightly uphill drive eastward on Sol 960 (Nov. 2nd, 2023) put Perseverance at Airey Hill, an exposure of the curvilinear-like rocks. Perseverance will be parked here for the duration of solar conjunction. Upon arrival at Airey Hill, the team has been focused on characterizing the surrounding rocks with remote sensing observations, including an enormous Mastcam-Z 360 degree stereo panorama acquired at the highest resolution (110 mm focal length). In addition to characterizing the rocks, Perseverance has also been busy monitoring the Martian atmosphere to look for clouds and dust devils, as well as acquiring environmental measurements with the MEDA (Mars Environmental Dynamics Analyzer) instrument.

While Perseverance’s co-workers back on Earth will be taking a well-deserved break from surface operations, the rover will be keeping busy over the next few weeks by collecting weather measurements, surveying for clouds and dust devils, monitoring changes in the nearby rocks and soils, collecting sounds with its microphones, and conducting stationary experiments with the RIMFAX (Radar Imager for Mars’ Subsurface Experiment) instrument.

Written by Brad Garczynski, Student Collaborator at Purdue University

There was a long delay between Flight 52 and Flight 53,  and a deviation from the published Flight 53 plan. I will address both in this blog post. First, the Flight 53 delay was the direct result of a decision by the team to fly Ingenuity out of telecom communications range with the rover. One may question the wisdom of this, but there are good reasons to do so. 

When plotting a traversal path through a given area, the team identifies a series of smooth, flat regions referred to as “lily pads” where the helicopter can safely land without significant risk of damage to the vehicle. Because the helicopter’s laser altimeter is fairly sensitive to large terrain variations, the team also generally tries to plan flight paths over the smoothest and flattest terrain available. These terrain types also happen to be the areas favored by rover planners as they are more easily traversable and contain fewer obstacles that might impede rover progress. The result is that in difficult terrain, the two vehicles generally compete for the same narrow path. 

Roughly speaking, the Ingenuity team’s top mission priorities are:

1 – Avoid significant interference with, or delay of, rover operations 

2 – Maintain vehicle health and safety

3 – Perform scouting for tactical planning and science assessment

4 – Perform experiments to inform mission and vehicle design for future Mars rotorcraft, or collect data for discretionary science

In difficult terrain, the first two priorities result in an emphasis on staying well ahead of Perseverance. Staying only slightly ahead of the rover while providing good data transfer rates is risky since the helicopter may inadvertently block the rover’s path. Staying just behind the rover is also a challenge, as the flight paths of the helicopter would need to be too close to the rover for safety or incorporate energy-sapping diverts to maintain adequate distance. Staying to the side of the rover is often not possible due to communications and landing-site constraints. Staying far behind the rover obviously risks loss of telecom, which would force the rover to reverse (violating priority #1) or leave the helicopter behind (violating priority #2). Thus, the helicopter frequently operates in a narrow slice of terrain several hundred meters ahead of the rover’s position. When telecom permits, the team will try to land at locations parallel to Perseverance’s planned strategic route, but this has been the exception, not the rule over the last year of the mission.

This balancing act require careful planning to maximize operational flexibility, agile replanning of flights/activities on short notice, and a high number of operations shifts focusing on file transfers to compensate for the poor data transfer speeds at the fringes of the radio’s range. Slow data transfer turnaround reduces the achievable flight cadence and operational effectiveness of the helicopter. 

Flying slightly ahead of telecom range is one strategy to cope with this environment, as it buys time, reducing the risk of rover interference and/or reducing the demand on the operations team to execute short-notice flights. This, however, has some drawbacks: 1) It further retards operation cadence, as it forces the helicopter to spend more time in regions with poor telecom. 2) It can potentially strand the helicopter beyond comms range if the rover encounters any delay or makes tactical decisions that deviate from the strategic route. This latter vulnerability came into play almost immediately after Ingenuity executed its 52nd flight. 

A Waiting Game

Flight 52 was planned as a long-distance, out-of-telecom flight, which was executed on Sol 776 with the expectation that the rover was nearing the end of its exploration at Echo Creek and would be approaching the helicopter’s resting spot near Mt. Julian within a few sols. The flight was performed exactly as planned, with Ingenuity losing radio link at approximately 8 meters (matching our telecom models). Still, the lack of successful landing confirmation meant that the downlinked telemetry for this flight was somewhat less reassuring than typical post-flight downlinks. The team settled in for what was supposed to be a brief but suspenseful wait for Perseverance to catch up and provide confirmation that the intrepid helicopter had landed safely.

Roughly a week later, the rover began moving, but instead of heading southeast toward Mt. Julian as planned, the science team had decided to perform an investigation of the area around Powell Peak. The Ingenuity team members, thankful for the unplanned break but still worrying about the unknown state of the helicopter, prepared for another week or two of waiting. Weeks soon turned into months as the rover overcame various challenges to its schedule. The poor structural integrity of the rock in the area foiled two sampling attempts before the rover team was able to successfully capture a sample on Sol 822 and successfully seal it 10 sols later. People following the rover’s activities will know that this campaign proved to be far more challenging than anyone imagined. Finally, after another week of activities, Perseverance was close enough to re-establish communications with Ingenuity on Sol 837.

In total, Ingenuity had been out of contact for 61 sols, an eternity when the outcome of the flight was unknown to the team. This marked the longest period of helicopter inactivity since Perseverance and Ingenuity landed on the planet. During this time, the Ingenuity team had largely deactivated, with members reallocating their time to work on other projects. 

As the team dusted off the cobwebs and started bringing down log files and images from the flight, it became apparent that the helicopter had spent the last two months parked on something truly remarkable. Sitting directly under Ingenuity’s feet, spread over the fractured rock of the riverbed, was a collection of cobbles and pebbles unlike any that scientists had seen before. Many were partially eroded and exhibited a vesicular texture more reminiscent of fresh basalt. These rocks immediately garnered a powerful reaction from project scientists, who requested that Ingenuity perform a dedicated science scouting flight as soon as possible.

The Science Flight That Wasn’t 

The team jumped at the rare opportunity to provide valuable and exciting advanced science reconnaissance, but the flight would eventually pan out in a very different way. Flight 53 was to be an extremely interesting flight with extensive RTE (color camera) imagery at low altitude to return a plethora high-resolution ground scans covering portions of the riverbed slightly north of the original landing location. Partway through the flight on Sol 864, however, a synchronization issue with the time-critical navigation camera triggered the “LAND-NOW” fault protection routine in the guidance navigation and control (GNC) subsystem. As the name implies, this caused Ingenuity to abort the flight and land immediately where it was.

Ingenuity corrects its spatial orientation estimate by tracking the movement of ground features within these navcam images, but these data must be perfectly time-synchronized with measurements from the inertial guidance system to provide valid corrections. In the case of Flight 53, this synchronization step mysteriously failed in a way that hadn’t been observed on any of the prior 52 flights on Mars or during the years of ground testing that preceded them. As of this writing, the precise cause is strongly suspected but has not been conclusively proven.

During the development phase of the mission, many fault responses were considered, but with a system as inherently unstable and time sensitive as a helicopter, the best response is almost always to land as soon as possible. Following the R8.0 software update in October of 2022, the fault response had been subtly changed. R8.0 included a new and valuable hazard-divert capability, allowing the helicopter to intelligently shift its landing target to avoid areas that appeared dangerous to its cameras. This update also applied the hazard-divert behavior to the LAND-NOW response. In what was surely a fortunate twist of fate, the GNC team had discovered a peculiar and potentially fatal interaction between these two behaviors just one month prior to flight. By the time of Flight 53, operational changes had been put in place mitigate the issue (preventing the use of hazard-diverts during emergency landings). The Flight 53 LAND-NOW executed precisely as designed, getting the helicopter on the ground quickly and safely. This event was unprecedented and is Ingenuity’s first emergency landing on Mars.

By the time the team had assessed the issue, Perseverance had caught up to the helicopter and passed it on Sol 871, removing the need to complete the imaging planned for Flight 53. Ingenuity returned to the skies of Mars with a short pop-up Flight 54 to get a fix on its location and then resumed its scouting duties at a new location with Flight 55 on Sol 881.

Parting Thoughts

The team is in a constant battle with minimizing and balancing various risks. Ingenuity was flown out of comms range to guard against the very likely possibility that project scientists would opt to head west immediately. This illustrates the difficulty in making effective plans when the ability to execute those plans is entirely dependent on another vehicle, itself subject to unexpected events. This is doubly true since the science mandate of Perseverance rightly dictates that its plans should change as new discoveries are made and new data become available. Even without these inherent coordination challenges, sometimes unexpected events can derail even the most well-laid plans as they did in Flight 53. No one on the project could have predicted the eventual outcome that resulted in the loss of two months of helicopter mission time and the unfortunate loss of one of the most exciting scouting flights in recent memory. Nevertheless, the helicopter will continue up the ancient river delta, balancing risks and providing scouting for the rover where possible. The two Mars vehicles will soon reach an area where the rover is scheduled to loiter for several months. This should significantly relax planning constraints and provide an opportunity for the helicopter to engage in a wider variety of activities. 

Written by Travis Brown, Chief Engineer Ingenuity Mars Helicopter at NASA's Jet Propulsion Laboratory

• Flight 66
• Expected flight date: 11/02/2023
• Horizontal flight distance: 0.5 meters
• Expected flight time: 23.38 seconds
• Flight altitude: 3 meters
• Heading: South
• Max flight speed: 1 m/s
• Goal of flight: Reposition the helicopter
• Airfield: Same