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At least 685 records · Page 38

Following the water, the new program for Mars exploration

In the wake of the loss of Mars Climate Orbiter and Mars Polar Lander in late 1999, NASA embarked on a major review of the failures and subsequently restructured all aspects of what was then called the Mars Surveyor Program--now renamed the Mars Exploration Program. This paper presents the process and results of this reexamination and defines a new approach which we have called "Program System Engineering". Emphasis is given to the scientific, technological, and programmatic strategies that were used to shape the new Program. A scientific approach known as "follow the water" is described, as is an exploration strategy we have called "seek--in situ--sample". An overview of the mission queue from continuing Mars Global Surveyor through a possible Mars Sample Return Mission launch in 2011 is provided. In addition, key proposed international collaborations, especially those between NASA, CNES and ASI are outlined, as is an approach for a robust telecommunications infrastructure. c2002 Published by Elsevier Science Ltd.

Water↗

Comparing 3D and 2D CFD for Mars Helicopter Ingenuity Rotor Performance Prediction

Single and coaxial rotor performance simulations for the Mars Helicopter Ingenuity rotor are performed for representative Mars atmospheric conditions. Analyses are presented using both a high-fidelity 3D CFD model of the rotor and 2D CFD models of the airfoil sections for comprehensive analyses that use CAMRADII (Comprehensive Analytical Model of Rotorcraft Aerodynamics and Dynamics). When available, the airfoil performance calculations are generated using a numerical approach identical to that used in the high-fidelity 3D model, allowing for a direct comparison between the approaches. Experimental data from a validation campaign to explore higher thrust from an Ingenuity rotor is provided to substantiate a discussion on the simulation fidelity required for both coaxial and single rotor performance predictions. The data is in support of the Sample Recovery Helicopter (SRH) element that serves as the primary backup for tube retrieval as part of the Mars Sample Return (MSR) Campaign. Insights on modeling turbulence at low Reynolds numbers and its influence on the rotor figure of merit are discussed. Key rotor performance metrics are compared. A detailed investigation into differences between 2D and 3D rotor performance predictions, spanwise loading, and rotor stall behavior is included.

Mars Helicopter↗

Increased Science Instrumentation Funding Strengthens Mars Program

As the strategic knowledge gaps mature for the exploration of Mars, Mars sample return (MSR), and Phobos/Deimos missions, one approach that becomes more probable involves smaller science instrumentation and integrated science suites. Recent technological advances provide the foundation for a significant evolution of instrumentation; however, the funding support is currently too small to fully utilize these advances. We propose that an increase in funding for instrumentation development occur in the near-term so that these foundational technologies can be applied. These instruments would directly address the significant knowledge gaps for humans to Mars orbit, humans to the Martian surface, and humans to Phobos/ Deimos. They would also address the topics covered by the Decadal Survey and the Mars scientific goals, objectives, investigations and priorities as stated by the MEPAG. We argue that an increase of science instrumentation funding would be of great benefit to the Mars program as well as the potential for human exploration of the Mars system. If the total non-Earth-related planetary science instrumentation budget were increased 100% it would not add an appreciable amount to the overall NASA budget and would provide the real potential for future breakthroughs. If such an approach were implemented in the near-term, NASA would benefit greatly in terms of science knowledge of the Mars, Phobos/Deimos system, exploration risk mitigation, technology development, and public interest.

Graham, Lee D.↗

The planetary exploration programme after two decades

The possible future of the United States program of planetary exploration in the next two decades is examined. The scientific goals and strategy for the exploration of the solar system outside of the earth-moon system are outlined, and the increasing cost effectiveness (per bit of data returned) of the first two decades of space exploration is pointed out. Attention is then given to the next two missions which are currently authorized and under development, the Galileo Jupiter orbiter and descent probe mission and the International Solar Polar Mission, and to possible missions for the next two decades, which would require additional thrust capabilities, including cometary missions, the Venus Orbiting Imaging Radar mission, a follow-on solar probe mission, a Saturn-Titan dual probe, and a Mars sample return mission.

James, J. N.↗

Entry System Design Considerations for Mars Landers

The objective for the next generation or Mars landers is to enable a safe landing at specific locations of scientific interest. The 1st generation entry, descent and landing systems, ex. Viking and Pathfinder, provided successful landing on Mars but by design were limited to large scale, 100s of km, landing sites with minimal local hazards. The 2 nd generation landers, or smart landers, will provide scientists with access to previously unachievable landing sites by providing precision landing to less than 10 km of a target landing site, with the ability to perform local hazard avoidance, and provide hazard tolerance. This 2nd generation EDL system can be utilized for a range of robotic missions with vehicles sized for science payloads from the small 25-70 kg, Viking, Pathfinder, Mars Polar Lander and Mars Exploration Rover-class, to the large robotic Mars Sample Return, 300 kg plus, science payloads. The 2nd generation system can also be extended to a 3nd generation EDL system with pinpoint landing, 10's of meters of landing accuracy, for more capable robotic or human missions. This paper will describe the design considerations for 2nd generation landers. These landers are currently being developed by a consortium of NASA centers, government agencies, industry and academic institutions. The extension of this system and additional considerations required for a 3nd generation human mission to Mars will be described.

Lockwood, Mary Kae↗

Mars Ascent Vehicle Hybrid PropulsionEffort

A technology development program was undertaken to determine if the benefits of hybrid rocket propulsion could be realized for a Mars Ascent Vehicle (MAV) application. Specifically, the goal of this program was to increase the Technology Readiness Level (TRL) of a hybrid propulsion system such that it could be considered for a potential Mars Sample Return Campaign. Over the course of approximately five years, a new, wax-based fuel was developed, characterized and tested with Mixed Oxides of Nitrogen (from MON-3 to MON-25). Various ignition mechanisms were tested and solid hypergolic additives were evaluated for their potential to ignite the hybrid motor. Several hot-fire test campaigns were completed at both sub- and full-scale. The technology development program was born out of a JPL study documented by Shotwell and Karp that identified the Single Stage to Orbit (SSTO) hybrid propulsion system for a potential Mars Ascent Vehicle to be the lowest Gross Lift Off Mass option from the ten configurations evaluated. Benefits of the hybrid option included its predicted favorable low temperature storage and operation behavior, high performance and ability to restart (enabling the SSTO). The main disadvantage of the hybrid option was its low TRL,as it essentially started as a blank sheet design with a new fuel development. Near the end of the technology development program, a Preliminary Architecture Assessment (PAA) was completed to evaluate a single-stage hybrid propulsion system and a two-stage solid propulsion system for a potential MAV. The solid propulsion system was selected for further study in 2019, primarily because of its flight heritage. While the hybrid technology development program made many strides, there was still a list of challenges to overcome. This paper will discuss the substantial progress and remaining challenges from the technology development effort from 2015 through 2019. This includes fuel development and reformulation, sub- and full-scale testing at Space Propulsion Group, full scale testing at Parabilis, full scale testing at Whittinghill Aerospace, hypergolic additive testing at Purdue and Penn State and the evaluation of adding hypergolic additives to a full-scale grain. It also includes a discussion of the design that resulted from the Preliminary Architecture Assessment.

hybrid rocket↗

Mars Ascent Vehicle Hybrid Propulsion Effort

A technology development program was undertaken to determine if the benefits of hybrid rocket propulsion could be realized for a Mars Ascent Vehicle (MAV) application. Specifically, the goal of this program was to increase the Technology Readiness Level (TRL) of a hybrid propulsion system such that it could be considered for a potential Mars Sample Return Campaign. Over the course of approximately five years, a new, wax-based fuel was developed, characterized and tested with Mixed Oxides of Nitrogen (from MON-3 to MON-25). Various ignition mechanisms were tested and solid hypergolic additives were evaluated for their potential to ignite the hybrid motor. Several hot-fire test campaigns were completed at both sub- and full-scale. The technology development program was born out of a JPL study documented by Shotwell and Karp that identified the Single Stage to Orbit (SSTO) hybrid propulsion system for a potential Mars Ascent Vehicle to be the lowest Gross Lift Off Mass option from the ten configurations evaluated. Benefits of the hybrid option included its predicted favorable low temperature storage and operation behavior, high performance and ability to restart (enabling the SSTO). The main disadvantage of the hybrid option was its low TRL, as it essentially started as a blank sheet design with a new fuel development. Near the end of the technology development program, a Preliminary Architecture Assessment (PAA) was completed to evaluate a single-stage hybrid propulsion system and a two-stage solid propulsion system for a potential MAV. The solid propulsion system was selected for further study in 2019, primarily because of its flight heritage. While the hybrid technology development program made many strides, there was still a list of challenges to overcome. This paper will discuss the substantial progress and remaining challenges from the technology development effort from 2015 through 2019. This includes fuel development and reformulation, sub- and full-scale testing at Space Propulsion Group, full scale testing at Parabilis, full scale testing at Whittinghill Aerospace, hypergolic additive testing at Purdue and Penn State and the evaluation of adding hypergolic additives to a fullscale grain. It also includes a discussion of the design that resulted from the Preliminary Architecture Assessment.

hybrid rocket↗

Reactive Sequencing for Autonomous Navigation Evolving from Phoenix Entry, Descent, and Landing

Virtual Machine Language (VML) is an award-winning advanced procedural sequencing language in use on NASA deep-space missions since 1997, and was used for the successful entry, descent, and landing (EDL) of the Phoenix spacecraft onto the surface of Mars. Phoenix EDL utilized a state-oriented operations architecture which executed within the constraints of the existing VML 2.0 flight capability, compatible with the linear "land or die" nature of the mission. The intricacies of Phoenix EDL included the planned discarding of portions of the vehicle, the complex communications management for relay through on-orbit assets, the presence of temporally indeterminate physical events, and the need to rapidly catch up four days of sequencing should a reboot of the spacecraft flight computer occur shortly before atmospheric entry. These formidable operational challenges led to new techniques for packaging and coordinating reusable sequences called blocks using one-way synchronization via VML sequencing global variable events. The coordinated blocks acted as an ensemble to land the spacecraft, while individually managing various elements in as simple a fashion as possible. This paper outlines prototype VML 2.1 flight capabilities that have evolved from the one-way synchronization techniques in order to implement even more ambitious autonomous mission capabilities. Target missions for these new capabilities include autonomous touch-and-go sampling of cometary and asteroidal bodies, lunar landing of robotic missions, and ultimately landing of crewed lunar vehicles. Close proximity guidance, navigation, and control operations, on-orbit rendezvous, and descent and landing events featured in these missions require elaborate abort capability, manifesting highly non-linear scenarios that are so complex as to overtax traditional sequencing, or even the sort of one-way coordinated sequencing used during EDL. Foreseeing advanced command and control needs for small body and lunar landing guidance, navigation and control scenarios, work began three years ago on substantial upgrades to VML that are now being exercised in scenarios for lunar landing and comet/asteroid rendezvous. The advanced state-based approach includes coordinated state transition machines with distributed decision-making logic. These state machines are not merely sequences - they are reactive logic constructs capable of autonomous decision making within a well-defined domain. Combined with the JPL's AutoNav software used on Deep Space 1 and Deep Impact, the system allows spacecraft to autonomously navigate to an unmapped surface, soft-contact, and either land or ascend. The state machine architecture enabled by VML 2.1 has successfully performed sampling missions and lunar descent missions in a simulated environment, and is progressing toward flight capability. The authors are also investigating using the VML 2.1 flight director architecture to perform autonomous activities like rendezvous with a passive hypothetical Mars sample return capsule. The approach being pursued is similar to the touch-and-go sampling state machines, with the added complications associated with the search for, physical capture of, and securing of a separate spacecraft. Complications include optically finding and tracking the Orbiting Sample Capsule (OSC), keeping the OSC illuminated, making orbital adjustments, and physically capturing the OSC. Other applications could include autonomous science collection and fault compensation.

asteroid↗

Parametric Thermal Soak Model for Earth Entry Vehicles

The analysis and design of an Earth Entry Vehicle (EEV) is multidisciplinary in nature, requiring the application many disciplines. An integrated tool called Multi Mission System Analysis for Planetary Entry Descent and Landing or M-SAPE is being developed as part of Entry Vehicle Technology project under In-Space Technology program. Integration of a multidisciplinary problem is a challenging task. Automation of the execution process and data transfer among disciplines can be accomplished to provide significant benefits. Thermal soak analysis and temperature predictions of various interior components of entry vehicle, including the impact foam and payload container are part of the solution that M-SAPE will offer to spacecraft designers. The present paper focuses on the thermal soak analysis of an entry vehicle design based on the Mars Sample Return entry vehicle geometry and discusses a technical approach to develop parametric models for thermal soak analysis that will be integrated into M-SAPE. One of the main objectives is to be able to identify the important parameters and to develop correlation coefficients so that, for a given trajectory, can estimate the peak payload temperature based on relevant trajectory parameters and vehicle geometry. The models are being developed for two primary thermal protection (TPS) materials: 1) carbon phenolic that was used for Galileo and Pioneer Venus probes and, 2) Phenolic Impregnated Carbon Ablator (PICA), TPS material for Mars Science Lab mission. Several representative trajectories were selected from a very large trade space to include in the thermal analysis in order to develop an effective parametric thermal soak model. The selected trajectories covered a wide range of heatload and heatflux combinations. Non-linear, fully transient, thermal finite element simulations were performed for the selected trajectories to generate the temperature histories at the interior of the vehicle. Figure 1 shows the finite element model that was used for the simulations. The results indicate that it takes several hours for the thermal energy to soak into the interior of the vehicle and achieve maximum payload temperatures. In addition, a strong correlation between the heatload and peak payload container temperature is observed that will help establishing the parametric thermal soak model.

Agrawal, Parul↗

Particulate Removal Using a CO2 Composite Spray Cleaning System

The Planetary Protection surface cleanliness requirements for potential Mars Sample Return hardware that would come in contact with Martian samples may be stricter than previous missions. The Jet Propulsion Laboratory has developed a new technology that will enable us to remove sub-micron size particles from critical hardware surfaces. A hand-held CO2 composite cleaning system was tested to verify its cleaning capabilities. This convenient, portable device can be used in cleanrooms for cleaning after rework or during spacecraft integration and assembly. It is environmentally safe and easy to use. This cleaning concept has the potential to be further developed into a robotic cleaning device on a Mars Lander to be used to clean sample acquisition or sample handling devices in situ. Contaminants of known sizes and concentrations, such as fluorescent microspheres and spores were deposited on common spacecraft material surfaces. The cleaning efficiency results will be presented and discussed.

carbon dioxide↗

Biosignature Preservation Potential of Sulfate-Rich Rocks From Hogwallow Flats, Jezero Crater, Mars

The Mars 2020 Perseverance Rover discovered fine grained sedimentary rocks in the Hogwallow Flats member of the Shenandoah Formation at the ~3.6- to 3.8-billion-year-old Jezero crater, Mars. Mudstones and sandstones at the 3-meter-thick Hogwallow Flats (HWF) outcrop, and a laterally equivalent outcrop known as “Yori Pass”, show extensive evidence of diagenesis (alteration after deposition). Enhanced preservation of organic matter and other biosignatures can occur in early diagenetic environments associated with aqueous alteration in a lake, floodplain or pro-deltaic setting, as envisaged for HWF and Yori Pass [1]. Three drilled rock cores were collected from HWF-type bedrock as part of the Mars Sample Return Program. They are considered to be the samples with the highest potential to preserve organic compounds and biosignatures out of all samples collected so far by Perseverance (as of mission Sol 1000) [2]. This work outlines the implications of diagenesis for biosignature preservation in rock samples for possible return to Earth.

Mars 2020↗

Issues and Concerns in Robotic Drilling

Exploration of the Martian subsurface will be essential in the search for life and water, given the desiccated and highly oxidized conditions on the surface. Discovery of these, at least in non-fossil form, is unlikely without drilling or other physical access to the subsurface. Hence subsurface access will be critical for both future in-situ science and Mars sample return. Drilling applications present many new challenges for diagnosis and control technology. Traditionally, diagnosis has concentrated on determining the internal state of a system, and detecting failures of system components. In the case of drilling applications, an additional challenge is to diagnose the interactions between the drill and its environment. This is necessary because particular observations of the drilling operation may be consistent with a number of possible problems, including faults in the equipment, but also changes in the material being drilled (for example, from rock to ice). The diagnosis of a particular observation may also depend on knowledge of geological formations previously encountered during drilling, and different remedial actions may be required for each diagnosis. Current 2009 Mars mission scenarios call for no more than 33 sols to be spent drilling. Yet they also call for a baseline of two 2m-deep holes in each of three target areas, for a total of six drilling operations. Using current levels of automation, it is estimated that 15-16 sols would be required to drill each hole. As a result of this, either the drilling part of the mission plan will need to be severely downscoped to no more than two holes total, or on-board automation and robotics must be increased in order to reduce the number of sols required per hole by removing ground control from the drilling control loop. This lecture will discuss salient issues and concerns of robotic drilling automation compares with other applications, and implementation constraints.

Glass, Brian↗

Detailed Design of an Earth Entry Vehicle for Comet Surface Sample Return

The 2013 Decadal Survey for New Frontiers missions identifies several high-value science missions, including Comet Surface Sample Return (CSSR). A CSSR mission will advance the scientific community's fundamental understanding of the origin of the solar system and the contribution of comets to the volatile inventory of the Earth. An entry capsule, or earth entry vehicle (EEV), is be required to protect the scientific payload from the extreme conditions of atmospheric entry, descent, and landing. The Decadal Survey Mission Concept Study along with an APL (Johns Hopkins University Applied Physics Lab) 2007-2008 Comet Surface Sample Mission Study details several of the driving requirements for a CSSR EEV; these include a payload volume and mass and inertial entry velocity of 9 kilometers per second. The mission concept study selected a Multi-Mission Earth Entry Vehicle (MMEEV) design concept derived from the Mars Sample Return (MSR) entry capsule design because of its increased reliability over a parachute-based vehicle. This presentation will explore detailed design of a CSSR-capable Earth Entry Vehicle, including trajectories, aeroheating predictions and associated thermal protection system masses, and onboard instrumentation for entry science.

Trajectory Analysis↗

Method for Cleanly and Precisely Breaking Off a Rock Core Using a Radial Compressive Force

The Mars Sample Return mission has the goal to drill, break off, and retain rock core samples. After some results gained from rock core mechanics testing, the realization that scoring teeth would cleanly break off the core after only a few millimeters of penetration, and noting that rocks are weak in tension, the idea was developed to use symmetric wedging teeth in compression to weaken and then break the core at the contact plane. This concept was developed as a response to the break-off and retention requirements. The wedges wrap around the estimated average diameter of the core to get as many contact locations as possible, and are then pushed inward, radially, through the core towards one another. This starts a crack and begins to apply opposing forces inside the core to propagate the crack across the plane of contact. The advantage is in the simplicity. Only two teeth are needed to break five varieties of Mars-like rock cores with limited penetration and reasonable forces. Its major advantage is that it does not require any length of rock to be attached to the parent in order to break the core at the desired location. Test data shows that some rocks break off on their own into segments or break off into discs. This idea would grab and retain a disc, push some discs upward and others out, or grab a segment, break it at the contact plane, and retain the portion inside of the device. It also does this with few moving parts in a simple, space-efficient design. This discovery could be implemented into a coring drill bit to precisely break off and retain any size rock core.

Richardson, Megan↗

Biomarkers in Carbonate Thermal Springs: Implications for Mars

Evidence of possible relict biogenic activity has been reported in carbonate inclusions within martian meteorite ALH 84001. The initial evidence included ovoid and elongated forms 50 - 500 nanometers in length, morphologically similar to but significantly smaller than many terrestrial microbes. More recently, thin structures resembling the remains of organic biofilms have been reported in the same meteorite. Carbonates have also been discussed in the context of Mars sample return missions. Thermal spring deposits have often been cited as prime locations for exobiological exploration. By analogy to Earth, specialized microbes may have existed in the heated, mineralized waters, and precipitates of carbonate and/or silica from these waters may have trapped and preserved evidence of life. Since the geological interactions that produce thermal springs can be recognized in orbital imagery, directed searches for microfossils in such deposits are deemed possible. We are engaged in a study of the signatures produced by contemporary biogenic activity (biomarkers) in carbonate thermal springs. We are examining the microbes that live in such environments and the preservation of microbial forms, biofilms, and petrographic fabrics indicative of life in thermal spring mineral deposits. This work is part of a much more extensive study to refine the appropriate tools, techniques, and approaches to seek evidence of life in a range of planetary samples. A deeper understanding of biological signatures will prepare us for the detailed search for life on Mars and eventually on other planets. Overall. the study of biomarkers in rocks and soils will provide insight into the evolution of life because such signatures are a record of how life interacts with its environment, how it adapts to changing conditions, and how life can influence geology and climate.

Allen, C. C.↗

New Developments In NASA’s Entry Systems Modeling Project

This paper describes recent developments for modeling entry, descent, and landing (EDL)of spacecraft in support of NASA’s exploration missions. Mission-specific research and model development for entry systems occurs across the Agency (e.g., within flight programs like Artemis/Orion and Mars Sample Return), however the aim of this paper is to discuss the research conducted by NASA’s Entry Systems Modeling (ESM) Project, which serves as the Agency’s only effort dedicated to advancing modeling capabilities that cross-cut multiple technical disciplines, missions and destinations. The ESM portfolio is developed to address the specific needs expressed by a cross-section of NASA stakeholders, including flight and research projects, technical leadership, and subject matter experts. Technology development in ESM is organized and prioritized from a system-level perspective, resulting in four broad technical areas of investment: (1) Thermal Protection System (TPS) material modeling, (2) Shock layer kinetics and radiation, (3) Aerosciences, and (4) Guidance, navigation, and control. In addition to the core technical areas, special topics are rolled into the project portfolio as specific demands arise. Current special topics include TPS Certification by Analysis, improving understanding of woven TPS material performance; Hypersonic Wake Flows, assessing and improving predictions of base flows; and the MEDLI2 Deep Dive, furthering analysis of data obtained during Mars2020 mission’s entry and descent at Mars. Key results from each of these areas are presented in this paper, along with associated references to serve as a roadmap for other EDL researchers to access NASA’s publications.

Aaron M Brandis↗

Performance Analysis and Data Processing for the Mars Sample Recovery Helicopter in the Jet Propulsion Laboratory 25-ft Space Simulator

On April 19, 2021, Ingenuity became the first helicopter to fly on Mars at Jezero Crater, completing a total of 72 flights by the end of its mission. The success of Ingenuity resulted in various research efforts to further explore Mars via vertical flight, including two optimized Ingenuity-sized helicopters proposed to retrieve samples for the 2028 Mars Sample Return mission. To aid in the design process for the two proposed Sample Retrieval Helicopters, both heritage and optimized, increased diameter rotors were tested at the NASA Jet Propulsion Laboratory in the 25-ft Space Simulator. Three test campaigns were performed using the Ingenuity rotors and optimized Sample Retrieval Helicopter (SRH) rotors for several rotor speeds, densities, configurations, and collectives to identify performance limitations. These three test campaigns included the Ingenuity Engineering Design Model 1 (EDM-1) with and without a cruciform box, Transonic Rotor Test (TRT) rig, and SRH Dual Rotor Test (DRT). Experimental setup, test matrix, data processing, data quality, and performance results for EDM-1, TRT, and DRT campaigns are presented and discussed. Experimental results from the test campaigns will aid in future experimental methods and validation efforts for planetary rotorcraft exploration.

Data Processing↗

Exploring the Jezero Delta Front: Overview of Results From the Mars 2020 Perseverance Rover’s Second Science Campaign

The Perseverance rover landed in Jezero crater on February 18, 2021, with the mission goals to explore the geology, astrobiological potential, and modern environment of the crater floor and delta, and to collect and cache well-documented samples for Mars Sample Return. After completion of the “Crater Floor” science campaign, the rover conducted a rapid traverse (sols 379-414) to the Three Forks region of the crater floor adjacent to the delta front. From here, Perseverance’s second “Delta Front” science campaign (DFC) began on Sol 415, April 20, 2022. The DFC has explored two lobes of the delta front, the neighboring crater floor, and their contact zone, focusing on the lowest geologic exposures composing the Jezero delta (largely mapped within the delta “thin layered unit”). As of January 1, 2023, Perseverance has covered 14325 km of traverse distance and collected 15 rock sample cores, 2 regolith samples, 1 atmospheric sample, and 3 witness tubes, employing a sample pair strategy where each unique sample is paired with a companion sample core from the same location, to enable the construction of two different caches. After sample depot construction at Three Forks, the DFC will conclude upon re-ascent of the delta front, and the next “Delta Top” science campaign will start.

Mars 2020 Mission↗