Search NASA⌕ Search

SEARCH · Search NASA

Results for “PLANETARY”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Planetary Protection Lunar Policy: A Case Study in Balancing COSPAR Guidelines, Scientific Consensus, NASA Policy, and Mission Implementation

With the increase of missions to the Earth’s Moon over the next decade, NASA initiated an assessment and review of the policy and protection of Earth’s Moon to enable scientific exploration. The assessment involved gathering scientific consensus regarding the Earth’s Moon and proposed mission operations considering an understanding of the desired science needs for the Moon. This process involved seeking advice from the National Academies of Science, Engineering, and Medicine’s (NASEM) Committee on Planetary Protection, engagement with the Committee on Space Research (COSPAR) Planetary Protection Panel (PPP), and consultation within NASA. To begin this process, NASA issued a NASA Interim Directive (NID) 8715.128 entitled, “Planetary Protection Categorization for Robotic and Crewed Missions to the Earth’s Moon” in July of 2019. This NID defined sensitive regions (e.g., permanently shadowed regions) on the Moon and required reporting on missions to these sensitive areas. Meanwhile, a NASEM study on the impact of human activities on lunar polar volatiles and the scientific value of protecting the surface and subsurface regions of the Earth’s Moon from organic and biological contamination was initiated. This resulted in a NASEM report entitled, “Planetary Protection for the Study of Lunar Volatiles” which enabled further dialogue within NASA and with COSPAR. COSPAR PPP then leveraged this scientific consensus along with multi-agency input to develop an updated COSPAR Policy on Planetary Protection in June 2021 resulting in updated mission categorizations for Earth’s Moon (existing Category II for orbiters, and new categories IIa and IIb for landed missions). NASA then updated its current planetary protection policy to apply directly to NASA and NASA partnered missions in NASA Procedural Requirements (NPR) 8715.24 entitled, “Planetary Protection Provisions for Robotic Extraterrestrial Missions”. Along with the policy update NASA’s Office of Planetary Protection has worked with mission and programmatic teams to streamline reporting requirements to a simplified checkbox and fill-in-the-blank type of template. Throughout the abovementioned process, open and transparent communication between the policy makers and implementers was essential to ensure a balance with the updated policy, scientific intent, and practicality for each mission to be responsive and achieve mission success, including Artemis I and each of its secondary payloads, Gateway, CAPSTONE and Lunar Trailblazer.

James Benardini↗
NASA NTRSDate not supplied

NASA’s Planetary Protection Program to Assure Mission Safety and Success

NASA’s planetary protection program seeks to understand and control harmful contamination of solar systems targets of exploration by terrestrial contamination and prevent harmful biological contamination of the Earth-Moon system by extraterrestrial life, should it exist. To accomplish these objective’s NASA has developed a balanced safety and mission assurance strategy that leverages COSPAR Policy guidelines, workshops, scientific consensus, partnerships and international working groups to develop policy and implementation guidelines. Upcoming crewed missions to the Moon and Mars, as well as robotic missions to small solar system bodies, Europa, Titan and Mars are some of the driving activities of astrobiological interest that continue to emphasize the importance of planetary protection throughout the project life cycle. Development of a responsive and updated agency planetary protection policy has been a focus area in supporting upcoming mission opportunities for exploration to include Mars sample return and crewed mission concepts. An extensive update of this policy is underway which encompasses crewed and robotic procedural polices, a general technical requirements standard, and an implementation handbook. During this timeframe NASA has been working with the international community to develop scientific consensus, and to identify and fill in knowledge gaps for developing balanced policy guidelines, incorporation of risk informed decision making and quantitative technical standards. NASA has developed a planetary protection roadmap as a technology management strategy to track and monitor the development of each knowledge gaps. The Committee of Space Research (COSPAR) Policy on Planetary Protection and the National Academies of Science, Engineering, and Medicine’s Committee of Planetary Protection are used to inform updates to the planetary protection polices and guidelines. This integrated strategy for planetary protection seeks to provide a transparent, structured approach for enabling missions, providing guidance for NASA and NASA partnered missions, and being responsive to the increased interest and activities in space exploration whilst maintaining an understanding and control of harmful contamination.

James Benardini↗
NASA NTRS2022

NASA’s Revised Planetary Protection Policy and Implementation

NASA has updated its planetary protection policy and implementation approach in response to advances in scientific understanding of solar system targets, upcoming mission opportuni-ties for exploration and sample return, and the private sector’s emerging capability to plan missions to Earth’s Moon and Mars. In September 2021, the NASA Procedural Requirements NPR 8715.24, entitled “Planetary Protection Provisions for Robotic Extraterrestrial Missions” was released which repositions planetary protection in existing NASA mission and program management structures, introduces risk-informed decision making, expands on key roles and responsibilities for both programmatic and the Oÿce of Safety and Mission Assurance, updates the categorization process and streamlines the planetary protection documentation approval and schedule. NASA is working on a more detailed technical standard to accompany NPR 8715.24 which will include the detailed technical requirements to address organic contamina-tion, inadvertent impact avoidance, biological control and management, end of mission disposal and restricted Earth-Return sample safety and assurance. This report to the COSPAR com-munity will describe the current NASA planetary protection policy and its alignment with the revised COSPAR planetary protection policy. NASA’s plans for updating the supporting “Handbook for Implementing Planetary Protection Technical Requirements” and future policies for addressing planetary protection of crewed missions will also be presented.

Elaine Seasly↗
NASA NTRS2022

NASA’s Revised Planetary Protection Policy and Implementation

NASA has updated its planetary protection policy and implementation approach in response to advances in scientific understanding of solar system targets, upcoming mission opportunities for exploration and sample return, and the private sector’s emerging capability to plan missions to Earth’s Moon and Mars. In September 2021, the NASA Procedural Requirements NPR 8715.24, entitled “Planetary Protection Provisions for Robotic Extraterrestrial Missions” was released which repositions planetary protection in existing NASA mission and program management structures, introduces risk-informed decision making, expands on key roles and responsibilities for both programmatic and the Office of Safety and Mission Assurance, updates the categorization process and streamlines the planetary protection documentation approval and schedule. NASA is working on a more detailed technical standard to accompany NPR 8715.24 which will include the detailed technical requirements to address organic contamination, inadvertent impact avoidance, biological control and management, end of mission disposal and restricted Earth-Return sample safety and assurance. This report to the COSPAR community will describe the current NASA planetary protection policy and its alignment with the revised COSPAR planetary protection policy. NASA’s plans for updating the supporting “Handbook for Implementing Planetary Protection Technical Requirements” and future policies for addressing planetary protection of crewed missions will also be presented.

Elaine Seasly↗
NASA NTRSDate not supplied

What You Need to Know about Planetary Protection Categorization for Your Mission

Planetary protection mission categorization helps to define the risk posture for requirements definition and implementation practices on space flight projects with planetary protection considerations. NASA has recently updated it’s planetary protection policy (NPR 8715.24), and with the update comes a major change in how the planetary protection categorization process is performed for NASA missions. Previously, projects would request the NASA Planetary Protection Officer (PPO) provide a categorization letter documenting the planetary protection category assigned to the proposed mission. Under the new policy the project manager (PM) proposes the planetary protection category for their mission. Depending on the level of the category, the PPO either concurs or recommends concurrence to the Chief of Safety and Mission Assurance (SMA) before forwarding to the Mission Directorate Associate Administrator (MDAA) for final approval prior to the system requirements review (SRR). But what topics must be considered for categorization? This presentation will provide key considerations for planetary protection mission categorization including the target solar system body to be explored, the trajectory to get to the target body, and the operations to be performed at the target body. Additional unique scenarios such as secondary and auxiliary payloads, encountering other solar system bodies on the way to the target body, and sample return missions will also be discussed to share lessons learned from missions that have been through the new categorization process.

Elaine Seasly↗
NASA NTRS2024

Results of the 2023 Mental Health Survey of the Planetary Science Community

Several recent studies have recognized mental health concerns in academia and in the research field more broadly [e.g., 1,2]. In planetary science, a 2022 survey found that the prevalence of clinically significant anxiety and depressive symptoms among our community is higher than in the general United States public, especially among graduate students, postdoctoral researchers, soft money researchers, and tenure-track faculty. Further, 76% of planetary science participants in the 2022 survey noted that their anxiety and/or depressive symptoms impacted their work, their ability to take care of things at home, and interpersonal relationships. Thus, these symptoms may play a role in decreased research quality and productivity. Interpretations of the 2022 mental health survey of planetary science also noted potential diversity, equity, and inclusion concerns. There were indications of statistically significant greater severities of anxiety, depression, and stress among women, people of color, and those who identify as LGBTQ+ compared to the dominant groups in planetary science. Furthermore, survey participants who identify as LGBTQ+ reported a greater likelihood of considering leaving the planetary science field. With the growing recognition of these mental health concerns, including evidence from the 2022 mental health survey of planetary science, the planetary science community advocated that NASA should further recognize the impact of mental health on science products and composition and work to address these issues including regular monitoring of the health of the community. With the 2023 survey, we shed light on the factors that may contribute to these mental health concerns, which may help the planetary science community and NASA on how to address the issue.

D Trang↗
DOE OSTI2021

Primary Velocity and Orbital Phase Effects on Planetary Detectability from Small Epoch Number Data Sets

Cross-correlation analyses of high-resolution spectroscopic data have recently shown great success in directly detecting planetary signals and enabling the characterization of their atmospheres. One such technique aims to observe a system at multiple epochs and combine the measured planetary radial velocities from each epoch into a measurement of the planetary Keplerian orbital velocity K {sub p}, constituting a direct detection of the planetary signal. Recent work has shown that in few-epoch (∼5) data sets, unintended structure can arise at a high level, obscuring the planetary detection. In this work, we look to simulations to examine whether there are ways to reduce this structured noise in few-epoch data sets by careful planning of observations. The choice of observation date allows observers to select the primary (stellar) velocity through a set systemic velocity and chosen barycentric velocity and the planetary orbital phase so we focus on the effects of these two parameters. We find that epochs taken when the primary velocity is near zero and the stellar lines remain relatively fixed to the telluric rest-frame greatly reduce the level of structured noise and allow for much stronger planetary detections, on average more than twice the significance of detections made with epochs using randomly selected primary velocities. Following these results, we recommend that observers looking to build up high-resolution multi-epoch data sets target nights when their system has a near-zero primary velocity.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
NASA NTRS1984

Planetary Data Definition

Planetary data include all of those data which have resulted from measurements made by the instruments carried aboard planetary exploration spacecraft, and (for our purposes) exclude observations of Moon and Earth. The working, planetary data base is envisioned to contain not only these data, but also a wide range of supporting measurements such as calibration files, navigation parameters, spacecraft engineering states, and the various Earth-based and laboratory measurements which provide the planetary research scientist with historical and comparative data. No convention exists across the disciplines of the planetary community for defining or naming the various levels through which data pass in the progression from a sensed impulse at the spacecraft to a reduced, calibrated, and/or analyzed element in a planetary data set. Terms such as EDR (experiment data record), RDR (reduced data record), and SEDR (supplementary experiment data record) imply different meanings depending on the data set under consideration. The development of standard terminology for the general levels of planetary data is necessary.

Source record↗
NASA NTRS1986

Influence of transient baroclinic eddies on planetary-scale waves

Low-order models with a mean zonal flow forced by zonally symmetric heating and one planetary-scale wave forced by topography have multiple flow equilibria. Two stable equilibria are characterized by strong zonal flow with low wave amplitude (high index circulation) and weak zonal flow with a high wave amplitude (low index circulation) fixed in phase with the topography. These two states presumably represent normal zonal circulation and a blocking configuration, respectively. When a shorter, baroclinically unstable wave is dded to this low-order model, the planetary-scale wave no longer stays in stable equilibrium states. Instead, the long wave remains in weather regimes or preferred regions in phase space. These regimes are, in general, different from the equilibria of the model with the planetary-scale wave only. Thus, the short unstable wave adds some randomness to planetary-scale circulation and changes its position with respect to the planetary-scale topography. The Reinhold and Pierrehumbert model is further explored here by adding a long-wave in the thermal forcing and exploring wider parameter space. When the symmetric thermal forcing is weak so that the short wave is stable, the planetary scale wave is fixed in amplitude and phase by the asymmetric forcing. However, when the symmetric forcing is increased to an unstable level, the planetary-scale wave becomes less organized. With asymmetric thermal forcing only (i.e., no topography) the long-wave is randomly distributed through phase space. Thermal forcing seems to be less effective in organizing weather regimes than topographic forcing.

Branscome, L. E.↗
NASA NTRS1994

Orbital coplanarity in solar-type binary systems: Implications for planetary system formation and detection

The equatorial inclinations of solar-type stars within visual binary systems are computed by combining v sin i measurements with rotational period information, or with expected rotational velocities based upon the age of the star in question. These inclinations are then compared with the orbital inclinations of the systems to test the alignment between the equatorial and orbital planes, and how the tendency for or against coplanarity varies as a function of parameters such as spectral type, separation, eccentricity, etc. The results are extended to planetary systems in order to determine the appropriateness of basing planetary search strategies upon a parent star's equatorial inclination, and to address issues in planetary system formation and evolution, including the stability of planetary orbits within binary systems. During the course of this project new or improved v sin i measurements are made for over 30 solar-type stars within binary systems, and (for the purposes of the study) tentative orbits are computed for thirteen long-period systems. The results suggest that approximate coplanarity between the equatorial and orbital planes exists solar-type binary systems with separations less than 30-40 AU. The coplanarity tendency, as well as this 'critical separation,' is not significantly affected by most of the other parameters studied. The one significant exception occurs with hierarchical multiple systems, where noncoplanarity may exist at relatively small separations. If it is assumed that planetary distances in our solar system are typical, the results suggest there is no reason to expect planets to orbit in planes significantly different from that of the parent star's equator, in turn suggesting that planetary formation models and search strategies dependent upon this assumption are valid from this standpoint. The results also suggest that noncoplanarity between the components of a binary system is not a significant issue in addressing the stability of planetary orbits within the system.

Hale, Alan↗
NASA NTRS1999

A Science Rationale for Mobility in Planetary Environments

For the last several decades, the Committee on Planetary and Lunar Exploration (COMPLEX) has advocated a systematic approach to exploration of the solar system; that is, the information and understanding resulting from one mission provide the scientific foundations that motivate subsequent, more elaborate investigations. COMPLEX's 1994 report, An Integrated Strategy for the Planetary Sciences: 1995-2010,1 advocated an approach to planetary studies emphasizing "hypothesizing and comprehending" rather than "cataloging and categorizing." More recently, NASA reports, including The Space Science Enterprise Strategic Plan2 and, in particular, Mission to the Solar System: Exploration and Discovery-A Mission and Technology Roadmap,3 have outlined comprehensive plans for planetary exploration during the next several decades. The missions outlined in these plans are both generally consistent with the priorities outlined in the Integrated Strategy and other NRC reports,4-5 and are replete with examples of devices embodying some degree of mobility in the form of rovers, robotic arms, and the like. Because the change in focus of planetary studies called for in the Integrated Strategy appears to require an evolutionary change in the technical means by which solar system exploration missions are conducted, the Space Studies Board charged COMPLEX to review the science that can be uniquely addressed by mobility in planetary environments. In particular, COMPLEX was asked to address the following questions: (1) What are the practical methods for achieving mobility? (2) For surface missions, what are the associated needs for sample acquisition? (3) What is the state of technology for planetary mobility in the United States and elsewhere, and what are the key requirements for technology development? (4) What terrestrial field demonstrations are required prior to spaceflight missions?

Source record↗
NASA NTRS1999

Formation and Detection of Planetary Systems

Modern theories of star and planet formation and of the orbital stability of planetary systems are described and used to discuss possible characteristics of undiscovered planetary systems. The most detailed models of planetary growth are based upon observations of planets and smaller bodies within our own Solar System and of young stars and their environments. Terrestrial planets are believed to grow via pairwise accretion until the spacing of planetary orbits becomes large enough that the configuration is stable for the age of the system. Giant planets begin their growth as do terrestrial planets, but they become massive enough that they are able to accumulate substantial amounts of gas before the protoplanetary disk dissipates. These models predict that rocky planets should form in orbit about most single stars. It is uncertain whether or not gas giant planet formation is common, because most protoplanetary disks may dissipate before solid planetary cores can grow large enough to gravitationally trap substantial quantities of gas. A potential hazard to planetary systems is radial decay of planetary orbits resulting from interactions with material within the disk. Planets more massive than Earth have the potential to decay the fastest, and may be able to sweep up smaller planets in their path. The implications of the giant planets found in recent radial velocity searches for the abundances of habitable planets are discussed, and the methods that are being used and planned for detecting and characterizing extrasolar planets are reviewed.

Lissauer, Jack J.↗
NASA NTRS2005

Influence of Planetary Protection Guidelines on Waste Management Operations

Newly outlined missions in the Space Exploration Initiative include extended human habitation on Mars. During these missions, large amounts of waste materials will be generated in solid, liquid and gaseous form. Returning these wastes to Earth will be extremely costly, and will therefore likely remain on Mars. Untreated, these wastes are a reservoir of live/dead organisms and molecules considered to be "biomarkers" i.e., indicators of life). If released to the planetary surface, these materials can potentially confound exobiology experiments and disrupt Martian ecology indefinitely (if existent). Waste management systems must therefore be specifically designed to control release of problematic materials both during the active phase of the mission, and for any specified post-mission duration. To effectively develop waste management requirements for Mars missions, planetary protection guidelines must first be established. While previous policies for Apollo lunar missions exist, it is anticipated that the increased probability of finding evidence of life on Mars, as well as the lengthy mission durations will initially lead to more conservative planetary protection measures. To facilitate the development of overall requirements for both waste management and planetary protection for future missions, a workshop was conducted to identify how these two areas interface, and to establish a preliminary set of planetary protection guidelines that address waste management operations. This paper provides background regarding past and current planetary protection and waste management issues, and their interactions. A summary of the recommended planetary protection guidelines, anticipated ramifications and research needs for waste management system design for both forward (Mars) and backward (Earth) contamination is also provided.

Hogan, John A.↗
NASA NTRS2013

Planetary Data Systems (PDS) Imaging Node Atlas II

The Planetary Image Atlas (PIA) is a Rich Internet Application (RIA) that serves planetary imaging data to the science community and the general public. PIA also utilizes the USGS Unified Planetary Coordinate system (UPC) and the on-Mars map server. The Atlas was designed to provide the ability to search and filter through greater than 8 million planetary image files. This software is a three-tier Web application that contains a search engine backend (MySQL, JAVA), Web service interface (SOAP) between server and client, and a GWT Google Maps API client front end. This application allows for the search, retrieval, and download of planetary images and associated meta-data from the following missions: 2001 Mars Odyssey, Cassini, Galileo, LCROSS, Lunar Reconnaissance Orbiter, Mars Exploration Rover, Mars Express, Magellan, Mars Global Surveyor, Mars Pathfinder, Mars Reconnaissance Orbiter, MESSENGER, Phoe nix, Viking Lander, Viking Orbiter, and Voyager. The Atlas utilizes the UPC to translate mission-specific coordinate systems into a unified coordinate system, allowing the end user to query across missions of similar targets. If desired, the end user can also use a mission-specific view of the Atlas. The mission-specific views rely on the same code base. This application is a major improvement over the initial version of the Planetary Image Atlas. It is a multi-mission search engine. This tool includes both basic and advanced search capabilities, providing a product search tool to interrogate the collection of planetary images. This tool lets the end user query information about each image, and ignores the data that the user has no interest in. Users can reduce the number of images to look at by defining an area of interest with latitude and longitude ranges.

Stanboli, Alice↗
NASA NTRS2018

Planetary Spectrum Generator: An Accurate Online Radiative Transfer Suite for Atmospheres, Comets, Small Bodies and Exoplanets

We have developed an online radiative-transfer suite (https://psg.gsfc.nasa.gov) applicable to a broad range of planetary objects (e.g., planets, moons, comets, asteroids, TNOs, KBOs, exoplanets). The Planetary Spectrum Generator (PSG) can synthesize planetary spectra (atmospheres and surfaces) for a broad range of wavelengths (UV/Vis/near-IR/IR/far-IR/THz/sub-mm/Radio) from any observatory (e.g., JWST, ALMA, Keck, SOFIA), any orbiter (e.g., ExoMars, Juno), or any lander (e.g., MSL). This is achieved by combining several state-of-the-art radiative transfer models, spectroscopic databases and planetary databases (i.e., climatological and orbital). PSG has a 3D (three-dimensional) orbital calculator for most bodies in the solar system, and all confirmed exoplanets, while the radiative-transfer models can ingest billions of spectral signatures for hundreds of species from several spectroscopic repositories. It integrates the latest radiative-transfer and scattering methods in order to compute high resolution spectra via line-by-line calculations, and utilizes the efficient correlated-k method at moderate resolutions, while for computing cometary spectra, PSG handles non-LTE and LTE excitation processes. PSG includes a realistic noise calculator that integrates several telescope/instrument configurations (e.g., interferometry, coronagraphs) and detector technologies (e.g., CCD, heterodyne detectors, bolometers). Such an integration of advanced spectroscopic methods into an online tool can greatly serve the planetary community, ultimately enabling the retrieval of planetary parameters from remote sensing data, efficient mission planning strategies, interpretation of current and future planetary data, calibration of spectroscopic data, and development of new instrument/spacecraft concepts.

Villanueva, G. L.↗
NASA NTRS2017

The Evolution of Planetary Protection Implementation on Mars Landed Missions

NASA has developed requirements dedicated to the prevention of forward and backward contamination during space exploration. Historically, international agreements provided guidelines to prevent contamination of the Moon and other celestial bodies, as well as the Earth (e.g., sample return missions). The UN Outer Space Treaty was established in 1967 and the Committee on Space Research (COSPAR) maintains a planetary protection policy complying with Article IX of this treaty. By avoiding forward contamination, the integrity of scientific exploration is preserved. Planetary Protection mission requirements are levied on missions to control contamination. These requirements are dependent on the science of the mission and on the celestial bodies encountered or targeted along the way. Consequently, categories are assigned to missions, and specific implementation plans are developed to meet the planetary protection requirements. NASA missions have evolved over time with increasingly more demanding scientific objectives and more complex flight systems to achieve those objectives and, thus, planetary protection methods and processes used for implementation have become much more intricate, complicated, and challenging. Here, we will portray the evolution of planetary protection implementation at JPL in several important areas throughout the course of NASA sponsored robotic Mars lander or rover missions, starting from Mars Pathfinder through the beginning of Mars 2020. Highlighted in the discussion will be process changes in planetary protection requirements development and flow down. Development and implementation of new and improved methods used in the reduction of spacecraft bioburden will be discussed as well as approaches and challenges that come along with setting up remote laboratories to perform bioassays. The consequences and forward planning of delays on missions will be highlighted as well as lessons learned on the impact of communication and training in achieving planetary protection requirements. The evolution of methods used for the detection of microbial bioburden on spacecraft hardware will be considered. These methods use standard microbiology as well as the adaptation of advances in biotechnology, molecular biology, and bioinformatics. Technical approaches developed for the prevention of contamination and recontamination of hardware during Assembly, Test, and Launch Operations will be discussed.

Kazarians, Gayane A.↗
NASA NTRS2019

Planetary Science with Small Satellites: Opportunities and Challenges

Small satellites aren't anything particularly new. Earth orbiting small satellites go back 30 years or more. What is new is the proliferation and access to small satellite technologies and flight opportunities. This has been in large part due to the advent of the "cubesat" model, initially a means to develop student's engineering skills, but has since evolved into an industry and accepted method within government space agencies. Until very recently these smallsats were limited to Earth orbiting missions, but with the successful flight of the MarCO spacecraft and the upcoming launch of EM-1 cubesats, the Moon, Mars and beyond are now within reach. While all this is good news, we still have a ways to go before smallsats become true planetary science tools. One could argue that Deep Space 2 was the first planetary smallsat, launched in 1999 and having a mass of 2.3 kg (each probe) it hoped to demonstrate that "real" science could be done with a small (and less expensive) package. The DS2 failure shelved the idea of smallsats (even chilling some to "Class D" planetary missions in general) for nearly two decades. NASA has slowly come back around to smallsats for planetary missions, going so far as to support a range of mission studies (the Planetary Science Deep Space SmallSat Studies, or PSDS3, Program) and the creation of a new Program (SIMPLEx) to developed such missions for opportunistic flights. The MarCO success was hugely important in maintaining (and building) this forward momentum. However, we still have yet to demonstrate "real" science from a planetary smallsat and there are some fundamental disconnects between expectation and reality. This talk will discuss some of the opportunities and challenges that reside with planetary smallsats, focusing on two examples: LunaH-Map (the first SIMPLEx cubesat) and Aeolus (a Mars PSDS3 smallsat concept).

Colaprete, Anthony↗
DOE OSTI2021

A Lattice Boltzmann Scheme for Polarized Radiative Transfer in Planetary Atmospheres

Quantitative calculation of reflected polarized light from planets is of great significance to interpret the polarimetric observations of planetary atmospheres. In this work, we propose a lattice Boltzmann (LB) scheme for polarized radiative transfer in planetary atmospheres. The LB scheme obtains the Stokes vector through the vector LB equation performing simple collision and streaming processes. The vector radiative transfer equation is rigorously derived from the vector LB equation via the Maxwell iteration technique. Polarized radiative transfer of a single point on the planetary surface with Rayleigh and Mie scattering atmospheres are first accurately solved by our LB scheme. Afterward, we systematically investigate the disk-integrated polarization of finite and semi-infinite, conservative and nonconservative Rayleigh scattering planetary atmospheres. The disk-integrated phase curves of the Stokes parameters and degree of polarization and spherical and geometric albedos are produced, which are in good agreement with the benchmark results for different cases. The numerical results indicate that our LB scheme is efficient and accurate for polarized radiative transfer in planetary atmospheres. Our LB scheme is expected to provide a competitive numerical tool to interpret the polarimetric observations of planetary atmospheres.

47 OTHER INSTRUMENTATION↗