cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.48577/jpl.0uaxxv
title: Salvaging Data Records with Missing Data, Part 2: Incorporating Imputation Bounds and the Power of Stan Hamiltonian Monte Carlo

description: When doing multivariate data analysis, one commonobstacle is the presence of incomplete observations, i.e., observationsfor which one or more key fields are missing data. Ratherthan deleting entire observations that contain missing data,which can lead to small sample sizes and biased inferences, dataimputation methods can be used to statistically “fill-in” missingdata. Imputing data can help combat small sample sizes byusing the existing information in partially complete observationswith the end goal of producing less biased and higher confidenceinferences. In addition, the knowledge contained within theincomplete observations is no longer lost when the partial datarecords are used, thus the effort spent collecting that data is notwasted effort.At the IEEE Aerospace Conference in 2021, we presented amethodology for imputing data using the Monotone Data Augmentation(MDA) algorithm, provided that the data followstwo assumptions: that it is missing at random (MAR) and itis approximately multivariate t-distributed. An example waspresented in the context of the NASA Instrument Cost Model(NICM), namely the NICM System Tool, which models the total(or system) cost of an instrument, typically as a function of thatinstrument’s total mass and power.In this paper, we outline the benefits of a fully Bayesian approachwhich samples simultaneously from the joint posteriordistribution of model parameters and the imputed values forthe missing data. This approach is preferred over multipleimputation approaches like MDA because it is more compatiblewith complex model forms and limited-range missing covariates.The new imputation approach is applied in two different waysin the NICM System Tool and NICM Subsystem Tool, as anexample to demonstrate the utility of the methods for usingknown bounds and improving model estimates. The examplemodels are implemented in Stan, a statistical-modeling toolenabling Hamiltonian Monte Carlo (HMC). The
DOI: 10.48577/jpl.flcgj8
title: Ingenuity, One Year of Flying on Mars

description: From Wright Brother’s Field out to South Séítah and Ingenuity’s subsequent mission traveling alongside Perseverance on its traverse to Jezero crater’s ancient river delta, this paper explores Ingenuity’s journey in the first year of its operational demonstration mission. Along the way, Ingenuity has scouted out the path ahead for Perseverance, imaged Perseverance’s backshell and parachute, and flown over 7 kilometers. With 33 completed flights to date, the team continues to push the vehicle’s limits and collect a rich set of flight and engineering data. Additionally, this paper will discuss Ingenuity’s loss of communication on sol 427, covering how the changing seasonal conditions caused Ingenuity’s survival heating to fail and the avionics to plunge below the designed operational temperatures in the Martian night. It will also discuss the process of recovering the vehicle, transitioning into low power winter operations, and returning to flight despite this anomaly, allowing the team to continue operating throughout the harshest environment Ingenuity has seen. Finally, it will detail vehicle and subsystem performance over the past year, as well as lessons learned from operating outside the bounds of the initial mission
DOI: 10.48577/jpl.xammfe
title: Cis-lunar space debris radar capability and feasibility

description: With NASA’s new focus on returning to the Moon, there is a need to build the capability to detect and track objects or debris that may threaten future missions in cis-lunar space. This paper analyzes the feasibility of detecting and tracking objects in cis-lunar space using NASA’s Deep Space Network’s (DSN) Goldstone Solar System Radar (GSSR) and the Green Bank Telescope (GBT). The GSSR is a 70-m antenna that can transmit X-band signals at 450kW. The cis-lunar space debris radar (CSDR) is a bistatic radar with the GSSR transmitting the signal and either the GBT (100-m diameter antenna) or a DSN 34-m antenna receiving the returned signal. The analysis will determine what object sizes are detectable under specific conditions and bistatic setups. Several GSSR, GBT, and DSN experiments were conducted to observe spacecraft in lunar orbit and xGEO (beyond GEO). The data from these experiments provide examples of detection versus tracking performance. Known spacecraft orbital dynamics will be compared with the radar estimated Dopplers, range, and signal-to-noise ratios (SNR). This analysis will look at the tradeoffs of waveforms traditionally used by GSSR, continuous wave (CW), and pseudorandom number (PN) codes and new ones considered for this application. With targets close to the Moon, return signals of certain waveform types are susceptible to interference from moon clutter.
DOI: 10.48577/jpl.lkowwi
title: Mars Sample Return Sample Handling Technology Development

description: The Decadal Survey strategy for Planetary Science and Astrobiology 2023-2032 recommended the development of a plan for effective end-to-end processing of samples returned from Mars. Key technologies were explored, traded, and conceptualized for fully contained sample handling of Mars samples within pristine isolators housed in a potential Sample Receiving Facility (SRF). These technologies include processes and hardware for both solid sample and head-gas sample removal from the Mars 2020 Returned Sample Tube Assemblies (RSTA), as well as a Secondary Outer Containment Case (SOCC) to provide additional prolonged protection of the sealed sample tubes during processing and storage. Hardware designs and end-to-end storyboards were developed. Full-scale mockups of the tooling were prototyped to evaluate hardware flow. Coupon testing was performed to demonstrate sealing, puncturing, and cutting processes, as well as characterize key design parameters.
DOI: 10.48577/jpl.zt1eko
title: Environmentally Invariant SiGe Electronics for On-Surface Exploration of Ocean Worlds

description: Exploration of Ocean Worlds (e.g., Europa) is especially challenging from an electronics perspective, given the combination of extreme radiation (5 Mrad TID) and low temperatures (-180°C) encountered on the surface. Legacy approaches (e.g., Mars rover) require placing electronics in protective “warm boxes” to ensure their robust operation, but this is not viable for Ocean Worlds given the constraints on battery life. From a mission-science perspective, it is highly desirable to utilize an electronics technology platform that possesses inherent “environmental invariance” (operates robustly in whatever environment it finds itself). The envisioned electronics platform should be commercially available, highly integrated, low-cost, support digital/analog/RF circuits, and bring compelling SWaP-C advantages. We are developing and demonstrating that advanced-node silicon-germanium (SiGe) electronics can support this vision. The SiGe NASA COLDTech team is working to demonstrate the efficacy of using SiGe technology to support NASA needs in this context (to TRL 5/6), and work to develop a design eco-system and component library for NASA utilization. Initial results are very encouraging.
DOI: 10.48577/jpl.fdctaf
title: Assessment of Contamination Ionization Due to Interaction with the Natural Environment for Gateway

description: NASA’s proposed Gateway is a space station that will orbit Earth’s moon. Outgassed contamination can cause degradation of Gateway components such as solar arrays, thermal control surfaces and science instruments. Interaction between outgassed material and the natural environment can lead to contamination ionization which can be driven back to Gateway by electric fields. The plasma in the Gateway lunar orbit has a density of 105 to 106 m-3 and the electron temperature is in the 10 to 30 eV range. Short duration high energy excursions with electron temperatures of 150 eV or greater and plasma densities 104 to 105 m-3 occur at the Gateway location. The sheath dimensions are on the order of 10 meters or larger at Gateway. Analysis was performed by solving the plasma sheath equations for Gateway. The expected contamination outgassing rate was used to estimate contamination ionizations rates within the sheath. The ionization rates were integrated throughout the sheath to determine the flux of ionized contaminates returning to Gateway. The susceptibility of various Gateway components to the ionized contamination flux can then be assessed to determine what if any mitigations are needed. The design is still evolving but mitigations can include materials selection to minimize outgassing and providing shielding or reorienting contamination sensitive surfaces.
DOI: 10.48577/jpl.knefbg
title: Using mm-wave observations to maximize the CRISTAL mission cryosphere science applications

description: Satellite observations are essential for monitoring changes in vast inaccessible polar regions. CRISTAL is the next polar altimetry mission being developed by the European Space Agency (ESA) and planned for launch in 2027. The payload includes an Interferometric Radar altimeter for Ice and Snow (IRIS, provided by ESA) operating at Ku- and Ka- bands and a potential NASA contribution of an Advanced Microwave Radiometer (AMR-CR) developed at NASA-JPL. The mission will include alongside AMR-CR, a High-Resolution Microwave Radiometer (HRMR). Together they provide radiometric measurement channels ranging from 18 to 166 GHz for open ocean topography and ice/snow applications. Changes in the polar regions have been widely documented by satellite microwave radiometer data. Frequencies up to 40 GHz are routinely used to derive sea ice extent, concentration, type, and thickness, as well as snow depth on sea ice. While higher frequency channels (mm-wave) provide improved spatial resolution, their use has been limited due to their sensitivity to atmospheric conditions and decreased penetration depths. For the first time, the CRISTAL mission will provide active and passive measurements of the polar regions over a wide range of frequencies. This new sensing capability will open up new avenues to explore novel cryosphere science that exploits the unique sensitivities of microwave and mm-wave observations to changes in atmospheric conditions and surface properties across a wide range of frequencies.
DOI: 10.48577/jpl.2s0tj9
title: Performance of Frequency Shift Keying for Low SEP Angle Communication

description: Communication during low Solar-Earth-Probe (SEP) angles generally suffers due to high scintillation effects. These effects are generally broken down into two categories: (1) Amplitude scintillation, and (2) Phase Scintillation. The amplitude scintillation effects have been studied and shown to be effectively modeled by wave interference. For scintillation indices under 1.0, it is usually modeled as a Rician random variable (approaching Rayleigh as the scintillation index approaches 1). The majority of the time, this results in destructive interference, effectively attenuating the signal amplitude. This can become a challenge for power constrained missions. The effect of the phase scintillation, however, is the introduction of random phase fluctuations on the intended received signal. This results in a bandwidth expansion of the desired signal and it generally (when in large quantities) renders phase-modulation schemes ineffective. In addition, these channel distorting effects generally refresh at a predictable period, which we denote as the coherence time of the channel. The spacecraft receiver must be able to cope with these effects in order to establish a reliable command link.In this paper, we evaluate the use of frequency shift keying (FSK) for communication during low SEP angles periods. The FSK waveform proposed is semi-coherent, which is important to the receiver operating through the scintillation effects (both amplitude and phase effects). The symbol-error-rate and bit error rates for the resulting communication scheme will be discussed as well. A GNU Radio implementation of an emulator for solar scintillation effects will be discussed. The parameters of the simulation, including scintillation index, coherence time, and models were derived from previous analysis of downlink signals during low SEP angle periods for other spacecraft, such as Cassini.
DOI: 10.48577/jpl.enc7x2
title: Demonstration of Autonomous Sampling Techniques in an Icy Moon Terrestrial Analog

description: A collection of functional autonomy behaviors to allow unsupervised science sample selection and collection on Icy Moons such as Europa or Enceladus was demonstrated on the terrestrial analog of Matanuska Glacier, AK, USA. Candidate sample sites are autonomously identified within the workspace, assessed for feasibility of successful collection, and surface material excavated while both preventing and responding to tool faults arising during interaction with the environment. A description of the system and lessons learned from the field application are discussed with respect to how they may impact potential future surface sampling missions to Icy Moons.
DOI: 10.48577/jpl.fge4yq
title: JSON-Based Sequencing For Deep Space Missions

description: Robotic deep space exploration missions, such asthose commonly operated by the NASA Jet PropulsionLaboratory, rely on “sequences” as the primary means ofnominal commanding. Each sequence is a unique file containingone or more commands that are timed to execute at some pointin the future – in this way, the operations team on the groundcan maintain control of the spacecraft through periods when itis out of contact, or when speed-of-light induced delay makesreal-time commanding impractical. Sequences are sent to aspacecraft in a binary format that is interpretable to theonboard computer, but must be developed on the ground in asource format which can be understood by human operators.The desired characteristics of a sequence source format areoften competing; it must be easily written and understood byhumans, but it also should be serializable to support automatedgeneration and review of sequences. The syntax and semanticsof the format must be unambiguously specified in a way that canbe communicated to disparate instrument and subsystemoperations teams that need to write and deliver sequences. Anecosystem of supporting software tools must be also be providedto operations teams to enable authoring, editing, simulation, andreview of sequences in the chosen format before they are sent tothe spacecraft. An inappropriate or poorly-designed sequencesource format has the potential to increase operations cost,hinder ground system automation efforts, confuse operationspersonnel, and lead to command errors during flight. TheEuropa Clipper and Psyche projects jointly developed theSeqJSON language as a new source format for spacecraftsequences, replacing legacy formats such as Spacecraft ActivitySequence File (SASF) and Spacecraft Activity Type File (SATF)that have been in use on deep space missions operated by the JetPropulsion Laboratory for decades. It is based on the JavaScriptObject Notation (JSON) format – a lightweight datainterchangeformat that is widely compatible with existingsoftware tools and programming languages. SeqJSONsequences are easy for humans to read, but also easy forsoftware to ingest, modify, and output. The syntax of SeqJSONsequences is fully specified by a JSON schema, which can beprovided to remote teams and used at their home institutions foron-premises sequence validation. The SeqJSON language wasdeveloped with Europa Clipper and Psyche onboard flightsoftware in mind, but it is applicable to any spacecraft that usestime-ordered sequences for commanding. This paper discussesthe SeqJSON language, how it differs from and improves uponlegacy formats, the operations paradigms it supports, thesoftware tools that facilitate its use, and the way it is being usedtoday.
DOI: 10.48577/jpl.ofkxm0
title: A comparative study of alternative rover configurations and mobility modes for planetary exploration

description: This paper reports on an experimental study to quantify the influence of the different adaptation capabilities that can be leveraged to improve the performance of low-cost four-wheeled rovers on sandy terrain. Conjointly with the ability to displace the center of mass and incline the rover's body, three configurations of passive suspensions and eight different locomotion modes are examined. The experiments are performed on sub-scale prototypes, with size, mass, and wheel geometry determined by a scaling analysis that ensures the consistency and transferability of the performance metrics to a 500 kg lunar rover equipped with 80 cm diameter wheels. The different configurations and locomotion modes are tested on GRC-1 lunar simulant on either a flat ground or a 20° slope, while climbing with a 0° or 45° angle of attack. The performance metrics observed are the travel reduction, the lateral deviation and the energy consumption.
DOI: 10.48577/jpl.25kbpu
title: Workflows, user interfaces, and algorithms for operations of autonomous spacecraft

description: Autonomous planning and scheduling is a key en- abling technology for future robotic Solar System explorers: as missions venture farther in the Solar System, light-speed delays and low available bandwidth make on-board autonomy increasingly attractive to maximize science returns and enable otherwise-infeasible observations of transient phenomena, e.g. storms on gas giants and plumes on icy worlds. However, ground operations of future autonomous explorers will require a paradigm shift, moving from the current practice of specifying timed sequences of commands, to specifying high-level goals that on-board autonomy should elaborate based on the spacecraft’s state and the sensed environment. In this paper, we explore the problem of adapting ground operations processes, roles, and tools to accommodate on-board planning and scheduling. We design and prototype a framework of user interfaces and algorithmic tools to support uplink and downlink processes of future autonomous spacecraft. The framework’s goals are to allow scientists and engineers to both convey their desired intent to the spacecraft in a format compatible with the on-board planner, and reconstruct and explain the decisions made on- board, and their impact on the state of the spacecraft. We assess the performance of the framework through a design simulation where JPL scientists and operators simulate realistic operations of an Ice Giant multi-flyby mission concept, aided by the tools we designed. The design simulation confirms that the proposed approach holds promise to enable operators to interact with on- board autonomy, and suggest a number of recommendations for the next generation of operations tools supporting autonomous spacecraft.
DOI: 10.48577/jpl.msmjsc
title: What Time is it at (16) Psyche?

description: The Psyche Project is a mission to the asteroid (16) Psyche, featuring three science instruments, a gravity science investigation, and a Deep Space Optical Communication technology demonstration. (16) Psyche, located in the asteroid belt between Mars and Jupiter, will be the first potential metal world—instead of rock or ice—visited by the National Aeronautics and Space Administration (NASA). This Jet Propulsion Laboratory (JPL) managed mission will explore Psyche after a 2023 or 2024 launch and a multi-year cruise. The mission uses a science instrument suite consisting of a pair of multispectral imagers, a gamma ray and neutron spectrometer, and a pair of magnetometers in a gradiometry arrangement.The Psyche timekeeping system is comprised of functions distributed throughout the Spacecraft, Payload, and Mission Systems. Readers will be introduced to the clocks and time systems used by the mission and the various correlation activities which transfer time knowledge between the Spacecraft Avionics and the ground and between the Spacecraft Avionics and the Payload instruments.This core of this paper provides a brief overview of the driving pointing control, pointing reconstruction, on-board ephemeris knowledge, and optical navigation requirements of the Psyche mission. Each of these requirements has a budget which suballocates the total allowable error to various sources, one of which is the timekeeping error. This paper will present a bottoms-up analysis of the timekeeping uncertainty for each driving pointing and navigation requirement for each phase of the mission. It will present the Project time budgets and walk through how each line item was calculated and the assumptions made in these calculations. The approaches and results of oscillator thermal stability, oscillator aging, flight system thermal performance, and avionics time correlation performance testing will be presented as supporting evidence of the time budget line items.The paper will provide readers an understanding of how to bound the uncertainty of reconstructed UTC measurement time, on-board ephemeris time knowledge, and predicted UTC command execution time for a deep space Spacecraft without an ultra-stable oscillator using the Psyche timekeeping architecture and mission plan as an example.
DOI: 10.5281/zenodo.10015135
title: French contemporary novel subgenre samples

description: Set of 30.000 short samples from 600 French novels first published between 1970 and 1999, and categorized by author, year of publication and subgenre.
DOI: 10.48577/jpl.vwteqe
title: The Evolution of Surface Preparation Tools for in Situ Science on Mars

description: Surface Preparation, or the act of removing the outside layer of a rock target, has been a scientific enabling engineering function of every Mars Rover since Spirit and Opportunity through the latest Perseverance Mars mission. Rock surfaces exposed to the harsh Martian environment can be covered in dust, and fundamentally changed in chemical composition due to exposure to weather and radiation. Surface preparation tools function to expose fresh layers of rock that are superior in providing an understanding of the processes in which they were formed, mineralogy, elemental chemistry, and exposing signs of organic chemistry. This paper describes the evolution of the robotic hardware and software designed, built, and flown in the series of NASA-led Martian Rover missions beginning with the Rock Abrasion Tool (RAT) on the Spirit/Opportunity rovers to the Dust Removal Tool (DRT) on Curiosity to the Corer & Gas Dust Removal Tool (gDRT) on the Perseverance Rover. The hardware design, concept of operation, and capabilities of each design are described herein. The driving requirements that shaped the hardware, and proved challenging to satisfy, are also detailed. Increasingly stringent performance requirements on each mission led to the progression of the hardware and software as well as new novel solutions to overcome performance challenges experienced on previous iterations. On the latest Perseverance Rover, this included a compressed gas system to clear dust tailings in lieu of brushes flown on previous missions, as well as an adaptive software algorithm that adjusts drill spindle speed, percussive energy, and surface pressure based on real-time sensor information to improve target surface smoothness and abrading bit wear characteristics. Selected Mars rock target results from each design iteration are provided. These images of previous Martian rock targets provide the best context to describe improvements in both our abrading capabilities and in our ability to clear tailings and dust from our abraded targets. The successes and shortcomings are discussed in relation to meeting the science community’s goals for interrogation of the abraded surface targets.
DOI: 10.5281/zenodo.10015134
title: French contemporary novel subgenre samples

description: Set of 30.000 short samples from 600 French novels first published between 1970 and 1999, and categorized by author, year of publication and subgenre.