Environments

Six operating environments, each set out as the engineering literature defines it: the design values hardware is built against, the model or measurement document each value comes from, and the conditions the value was taken under. Where a quantity is a property of the destination rather than of a vehicle, it is settled on one of these pages, and the robot, software, avionics and testing pages cite it rather than restate it.

The specifications and reference models that span more than one destination are listed under environment references. What a ground rig reproduces of any of these, and where its fidelity stops, is under test facilities.

How the environments differ as design problems

Three kinds of evidence sit behind the numbers on these pages, and they are not interchangeable. Surface values for the Moon and Mars come from flown measurement: Apollo-era soil and thermal properties from returned samples and two Soviet traverses [15], global regolith thermal inertia fitted to orbiter nighttime cooling curves [16], and Martian pressure, temperature, wind and opacity reduced from every landed meteorological record since Viking [18]. Values for the outer planets and small bodies come mostly from models and from a few probes: engineering atmosphere models built for aerocapture analysis [30], one descent that reached a surface [24], and one contact event that worked as a penetrometer [25]. Values for the Venus surface come from laboratory simulation alone, because no lander has operated there for long enough to supply a record [12].

The environments also constrain a vehicle through different terms. The Moon is set by the thermal and illumination cycle, Mars by dust and the communication delay, microgravity by the absence of a reliable weight, small bodies by cohesion in place of gravity, the outer planets by distance, and Venus by temperature and pressure that exceed what packaged electronics were qualified for.

What separates them

Microgravity and Orbital. Free fall is not zero acceleration. The residual field is treated as three bands separated by frequency: a quasi-steady band below 0.01 Hz, predictable anywhere in the vehicle from one measurement and the rigid-body kinematics, and vibratory content from 0.01 to 300 Hz and transient content, both of which have to be measured near the point of interest [2]. A disturbance catalog from Spacelab, SPACEHAB, the shuttle middeck and Mir attributes the content to named sources: crew exercise dominates roughly 1 to 4 Hz and pump activations produce transients near 1 mg [23]. Surface exposure is set by orientation rather than by altitude, and atomic oxygen fluence on LDEF was 8.81e21 atoms/cm2 on the ram face against 1.13e3 on the wake face, through 34,000 thermal cycles in 5.8 years [3]. Erosion yield is not a material constant: ram-facing MISSE yields for 71 materials span three orders of magnitude and some fall with fluence [22].
Lunar Surface. The equatorial surface runs between a mean maximum of 391 K at local noon and a mean minimum of 96 K before sunrise, and polar illumination follows no latitude rule, because local topography decides it [1]. Thermal inertia is not constant: it roughly doubles across an equatorial day, from 35 at midnight to 70 at noon [16]. For six candidate polar sites, simulated over an 18.6 year precession cycle, the best-illuminated clusters average 69.5 to 82.9 percent illumination at the surface, and the longest shadow is 20 to 50 percent of a lunar night [17]. The equatorial night lasts about 350 h, and warming a 70 kg rover back to its 243 K minimum operating temperature at dawn costs 452 to 493 W h of battery energy [4], so the unpowered interval sizes the thermal and power design. Soil design values (1.50 g/cm3 bulk density in the top 15 cm, 45 degree friction angle) come from a few hundred grams to a few kilograms of returned soil at six equatorial sites [15]. Round-trip communication is short enough to drive against: VIPER was designed around 6 to 10 s [5].
Martian Surface. Surface gravity is 3.712 m/s2, and the engineering atmosphere model is parameterized on solar longitude, latitude, longitude and local time rather than on calendar date, with dust storm intensity carried to an optical depth of 3 [6]. A gridded eight-year dust climatology puts the background equatorial column optical depth at 0.2 to 0.3 outside storm season [19]. Round-trip light time runs 5 to 40 min over the synodic cycle, which precludes real-time monitoring and is why the operations cycle is sol-based [7]. Ground tests also fail to predict flight behavior: the InSight mole reached 37 cm against a 3 to 5 m requirement because a cohesive duricrust supplied no hull friction, and penetration resistance exceeded 5 MPa where the ground testbed showed 0.2 to 0.5 MPa [20]. Radiation transport codes in a blind comparison against MSL-RAD differed from the measurement and from each other by a factor of two or more [21].
Small Bodies. Weight is not the dominant term in the surface mechanics. The grain radius at which van der Waals cohesion equals a grain’s own weight is 6.5e-4 m at 1 g and 0.65 m at micro-gravity, which makes the terrestrial analog a cohesive powder rather than a cohesionless soil, and net surface acceleration at Itokawa is 6 to 9 micro-G [8]. What a touch-and-go sampler meets changes character across an assumed regolith cohesive strength of about 50 to 300 Pa, between cratering with no spring engagement and a strength cone that stops the assembly at the surface [9]. The one direct force measurement is the OSIRIS-REx contact on Bennu: 5.95 to 6.91 cm of penetration at 10 to 15 N of resisting force, implying a near-subsurface bulk density of 440 to 600 kg/m3 [25]. Bennu also ejects particles at 0.05 to 3.3 m/s against a 0.2 m/s escape velocity, a proximity-operations hazard [26].
Outer Planets. Solar flux and communication rate fall as the inverse square of heliocentric distance, and round-trip light time runs to hours, so fault response cannot be supervised from Earth [10]. The two reachable surfaces are a giant planet entry corridor, where the Galileo probe met about 30 kW/cm2 of peak heating and 250 g of deceleration [11], and Titan, whose 1.35 m/s2 and dense cold atmosphere put rotorcraft flight power per unit mass at about a fortieth of the Earth value [10]. Titan and Neptune have scale heights near 40 km against about 10 km for Earth and Mars [30]. Huygens is the only descent to Titan’s surface; Dragonfly entry and descent simulations are checked against it, and the remaining nadir angle excursions trace to the zonal wind profile rather than the parachute model [24].
Venus Surface. About 460 C at roughly 90 bar of supercritical carbon dioxide with a sulfuric acid aerosol above it [12], which admits two design responses: a sealed and thermally isolated volume with a fixed lifetime, or electronics that operate at ambient temperature. A packaged alumina assembly has been held at 460 C and 92 bar in a simulated Venus atmosphere for 60 Earth days [13], though its insulation resistance fell by six orders of magnitude, and a silicon carbide JFET RAM has run 10,100 h at 500 C [14]. Scaling that technology from about 200 to about 1000 transistors per chip produced working converters and ROM but lower yield and durability than the chips behind the yearlong run [28]. All of this is laboratory evidence from chambers such as GEER, which holds roughly 500 C and 100 bar with nine gas streams [27], and whose users guide lists a feedthrough power limit and a six-week turnaround as the constraints that decide whether a given electronics test fits [29].

What is not established

Venus surface electronics have been exercised for at most 60 Earth days as a packaged assembly [13] and 10,100 h as a bare circuit [14], each from a single campaign, and the packaging degradation mechanism is proposed rather than demonstrated [13]. Small-body surface strength has one direct measurement, at one asteroid [25]. Radiation dose on the Martian surface is predicted to within a factor of two only at best [21]. Lunar soil properties rest on returned samples from equatorial sites, so polar values are inferred [15]. Operations numbers for the Mars rovers describe one team and one extended mission [7].

References

NASA. (2020). Cross-Program Design Specification for Natural Environments (DSNE), Revision G . NASA Marshall Space Flight Center. Source

BibTeX

@techreport{nasa2020cross,
  title = {Cross-Program Design Specification for Natural Environments (DSNE), Revision G},
  author = {{NASA}},
  institution = {NASA Marshall Space Flight Center},
  year = {2020},
  url = {https://ntrs.nasa.gov/citations/20200000867},
  abstract = {The DSNE completes environment-related specifications for architecture, system-level, and lower-tier documents by specifying the ranges of environmental conditions that must be accounted for by NASA ESD Programs. To assure clarity and consistency, and to prevent requirements documents from becoming cluttered with extensive amounts of technical material, natural environment specifications have been compiled into this document. The intent is to keep a unified specification for natural environments that each Program calls out for appropriate application.}
}

McPherson, K., Kelly, E. and Keller, J. (2009). Acceleration Environment of the International Space Station . AIAA Aerospace Sciences Meeting including The New Horizons Forum and Aerospace Exposition, 20120012936. Source

BibTeX

@inproceedings{mcpherson2009acceleration,
  title = {Acceleration Environment of the International Space Station},
  author = {McPherson, Kevin and Kelly, Eric and Keller, Jennifer},
  booktitle = {AIAA Aerospace Sciences Meeting including The New Horizons Forum and Aerospace Exposition},
  number = {20120012936},
  institution = {NASA},
  year = {2009},
  doi = {10.2514/6.2009-957},
  abstract = {Measurement of the microgravity acceleration environment on the International Space Station has been accomplished by two accelerometer systems since 2001. The Microgravity Acceleration Measurement System records the quasi-steady microgravity environment, including the influences of aerodynamic drag, vehicle rotation, and venting effects. Measurement of the vibratory/transient regime, comprised of vehicle, crew, and equipment disturbances, has been accomplished by the Space Acceleration Measurement System-II. Until the arrival of the Columbus Orbital Facility and the Japanese Experiment Module, the location of these sensors, and therefore, the measurement of the microgravity acceleration environment, has been limited to within the United States Laboratory. Japanese Aerospace Exploration Agency has developed a vibratory acceleration measurement system called the Microgravity Measurement Apparatus which will be deployed within the Japanese Experiment Module to make distributed measurements of the Japanese Experiment Module's vibratory acceleration environment. Two Space Acceleration Measurement System sensors from the United States Laboratory will be re-deployed to support vibratory acceleration data measurement within the Columbus Orbital Facility. The additional measurement opportunities resulting from the arrival of these new laboratories allows Principal Investigators with facilities located in these International Space Station research laboratories to obtain microgravity acceleration data in support of their sensitive experiments. The Principal Investigator Microgravity Services project, at NASA Glenn Research Center, in Cleveland, Ohio, has supported acceleration measurement systems and the microgravity scientific community through the processing, characterization, distribution, and archival of the microgravity acceleration data obtained from the International Space Station acceleration measurement systems. This paper summarizes the PIMS capabilities available to the International Space Station scientific community, introduces plans for extending microgravity analysis results to the newly arrived scientific laboratories, and provides summary information for known microgravity environment disturbers.}
}

Stein, B. A. (1992). An interim overview of LDEF materials findings . NASA, NASA-TM-107664. Source

BibTeX

@techreport{stein1992interim,
  title = {An interim overview of LDEF materials findings},
  author = {Stein, Brad A.},
  number = {NASA-TM-107664},
  institution = {NASA},
  year = {1992},
  url = {https://ntrs.nasa.gov/citations/19930009140},
  abstract = {The flight and retrieval of the National Aeronautics and Space Administration's Long Duration Exposure Facility (LDEF) provided an opportunity for the study of the low-Earth orbit (LEO) environment and long-duration space environmental effects (SEE) on materials that is unparalleled in the history of the U.S. Space Program. The remarkable flight attitude stability of LDEF enables specific analyses of various individual and combined effects of LEO environmental parameters on identical materials on the same space vehicle. This paper provides an overview of the interim LDEF materials findings of the Principal Investigators and the Materials Special Investigation Group. In general, the LDEF data is remarkably consistent; LDEF will provide a 'benchmark' for materials design data bases for satellites in low-Earth orbit. Some materials were identified to be encouragingly resistant to LEO SEE for 5.8 years; other 'space qualified' materials displayed significant environmental degradation. Molecular contamination was widespread; LDEF offers an unprecedented opportunity to provide a unified perspective of unmanned LEO spacecraft contamination mechanisms. New material development requirements for long-term LEO missions have been identified and current ground simulation testing methods/data for new, durable materials concepts can be validated with LDEF results. LDEF findings are already being integrated into the design of Space Station Freedom.}
}

Jones, H. L., Thornton, J. P., Balasubramaniam, R., Gokoglu, S. A., Sacksteder, K. R. and Whittaker, W. L. (2011). Enabling Long-Duration Lunar Equatorial Operations With Thermal Wadi Infrastructure . AIAA Aerospace Sciences Meeting including The New Horizons Forum and Aerospace Exposition, NASA/TM-2011-216994. Source

BibTeX

@inproceedings{jones2011enabling,
  title = {Enabling Long-Duration Lunar Equatorial Operations With Thermal Wadi Infrastructure},
  author = {Jones, Heather L. and Thornton, John P. and Balasubramaniam, Ramaswamy and Gokoglu, Suleyman A. and Sacksteder, Kurt R. and Whittaker, William L.},
  booktitle = {AIAA Aerospace Sciences Meeting including The New Horizons Forum and Aerospace Exposition},
  number = {NASA/TM-2011-216994},
  institution = {NASA Glenn Research Center},
  year = {2011},
  doi = {10.2514/6.2011-703},
  abstract = {Long duration missions on the Moon’s equator must survive lunar nights. With 350 hr of cryogenic temperatures, lunar nights present a challenge to robotic survival. Insulation is imperfect, so it is not possible to passively contain enough heat to stay warm through the night. Components that enable mobility, environmental sensing and solar power generation must be exposed, and they leak heat. Small, lightweight rovers cannot store enough energy to warm components throughout the night without some external source of heat or power. Thermal wadis, however, can act as external heat sources to keep robots warm through the lunar night. Electrical power can also be provided to rovers during the night from batteries stored in the ground beside wadis. Buried batteries can be warmed by the wadi’s heat. Results from analysis of the interaction between a rover and a wadi are presented. A detailed three-dimensional (3D) thermal model and an easily configurable two-dimensional (2D) thermal model are used for analysis.}
}

Mirmalek, Z., Lim, D. S., Colaprete, A. and Lees, D. (2025). Lunar science real-time operations and mission systems integration definitions and practices from NASA's VIPER mission . International Conference on Space Operations, SpaceOps-2025, ID 294. Source

BibTeX

@inproceedings{mirmalek2025lunar,
  title = {Lunar science real-time operations and mission systems integration definitions and practices from NASA's VIPER mission},
  author = {Mirmalek, Zara and Lim, Darlene S. and Colaprete, Anthony and Lees, David},
  booktitle = {International Conference on Space Operations},
  number = {SpaceOps-2025, ID 294},
  institution = {NASA},
  address = {Montreal, Canada},
  year = {2025},
  doi = {10.82217/spaceops2025_294},
  abstract = {Mission system design for the National Aeronautics and Space Administration (NASA) Volatiles Investigating Polar Exploration Rover (VIPER) mission began with focusing on building key components including a solar-powered rover and the ground data system for operating it on the Moon for 100-Earth-days. The VIPER mission would be designed to support teams of people on Earth and a robot on the Moon carrying out a scientifically planned search for water ice, over a distance of 20 km. Initially, within the mission system design the involvement of VIPER’s science team (VST) was noted as “the science customer” - a designation and acknowledgement of a key workgroup in the mission. The VST’s work support needs, for a science work system, however, had not yet been defined by the VST in terms of systems and architecture. As the VST’s Science Operations team conducted research to develop a science operations system and architecture for VIPER’s science mission activities they found the science system needs for supporting real-time lunar science were greater than that which was designated in the mission system for the science customer. They decided to focus on developing the science operations system via ongoing integration rather than establishing a separate science component that later would be adjoined to the mission system. VIPER Science Operations enacted integration as an ongoing work practice; integration was a carried out as a regular activity that required schedule and agenda planning to be carried out on a daily and weekly basis, and adjustments in accordance with other workgroups’ activities. The work of integrating requires including and maintaining a greater number of considerations in the short-term work plan such as scheduling and product considerations (e.g., goals, interface features, networks, workspace build, mission simulations) and human relationships. In the long-term, ongoing integration approach can yield benefits that include fewer system conflicts, which can be avoided by learning of conflicts during development when they can be addressed. In addition to lunar science operations development and training with the VIPER Science team, integration included working with VIPER Mission system’s operating software workgroup, as well as the workgroups for rover drivers, planning and timelining, mission systems engineering, testing and training, and mission workspace preparation. This paper shows the work of integration as a process during the pre- surface operations development stage and highlights some examples of mission enhancing decisions that resulted from this integrated approach.}
}

Justh, H. L., Burns, K. L., Dutta, S. and Hoffman, J. (2024). Mars Global Reference Atmospheric Model (Mars-GRAM) 2024: User Guide . NASA Marshall Space Flight Center. Source

BibTeX

@techreport{nasa2024mars,
  title = {Mars Global Reference Atmospheric Model (Mars-GRAM) 2024: User Guide},
  author = {Justh, Hilary L. and Burns, K. L. and Dutta, Soumyo and Hoffman, J.},
  institution = {NASA Marshall Space Flight Center},
  year = {2024},
  url = {https://ntrs.nasa.gov/citations/20240012934},
  abstract = {This Technical Memorandum (TM) presents the Mars Global Reference Atmospheric Model (Mars-GRAM) 2024 and its updated features. Mars-GRAM is an engineering-oriented atmospheric model that estimates mean values and statistical variations of atmospheric properties for Mars. This TM summarizes the atmospheric data model in Mars-GRAM and provides a guide for the user to obtain, set up, and run the code in various configurations. Additional details regarding the Mars-GRAM input and output files and how to interpret Mars-GRAM results are also provided.}
}

Gildner, M., Allbaugh, A. R., Mishkin, A., Algermissen, S., Kirk, M. V., Ellison, D., Bridge, C., Stough, T. and Stroupe, A. (2021). Commanding Curiosity from the Couch: MSL Remote Operations, Challenges, and Path Ahead . IEEE Aerospace Conference. Source

BibTeX

@inproceedings{gildner2021commanding,
  title = {Commanding Curiosity from the Couch: MSL Remote Operations, Challenges, and Path Ahead},
  author = {Gildner, Matthew and Allbaugh, Alicia R and Mishkin, Andrew and Algermissen, Stirling and Kirk, Matthew Van and Ellison, Douglas and Bridge, Carrie and Stough, Timothy and Stroupe, Ashley},
  booktitle = {IEEE Aerospace Conference},
  pages = {1-19},
  publisher = {IEEE},
  year = {2021},
  doi = {10.1109/aero50100.2021.9438370},
  abstract = {This paper describes how the Mars Science Laboratory (MSL) project prepared for and successfully began Curiosity rover Mars operations from their homes in response to the COVID-19 work-from-home orders. In a very short period, the team developed procedures and executed a remote operations readiness test in parallel with the team's support for nominal operations. Continuing regular rover operations with an entirely remote team had not previously been considered feasible due to a variety of factors. These included both the human factors, such as multiple concurrent person-to-person interactions of the uplink planning team, as well as technical factors, such as reliance on powerful workstations dedicated to graphically intensive software tools used for planning. The test was conducted on March 12, 2020, with both the downlink and uplink teams successfully simulating a near full planning day. The JPL administration announced the transition to mandatory telework on Monday, March 16. MSL stood down the uplink planning originally scheduled for the next day while downlink continued monitoring the rover. Full operations then resumed per schedule with nearly the entire operations team teleworking on Friday, March 20, during which the team planned rover activities for three Martian days (sols). These activities included the successful drilling of the “Edinburgh” rock target, a highly complex robotic arm contact science activity. As of October 1, 2020, the Mars Science Laboratory mission operations team has conducted 88 remote tactical uplink shifts for a total of 190 sols of planned rover activity, which accounts for more than 6% of the mission to date. In this period the rover has completed four drilling campaigns and driven over 1160 meters towards its next major science target - a sulfate bearing geologic unit at the foot of Mount Sharp. Success has not been without its challenges. Many of these have been addressed while others will remain in some form until the team can safely return to JPL, which in turn is the largest challenge for the future.}
}

Scheeres, D. J., Hartzell, C. M., Sánchez, P. and Swift, M. (2010). Scaling forces to asteroid surfaces: The role of cohesion . Icarus. Source

BibTeX

@article{scheeres2010scaling,
  title = {Scaling forces to asteroid surfaces: The role of cohesion},
  author = {Scheeres, Daniel J. and Hartzell, C. M. and Sánchez, Paul and Swift, M.},
  journal = {Icarus},
  volume = {210},
  pages = {968--984},
  year = {2010},
  doi = {10.1016/j.icarus.2010.07.009}
}

Scheeres, D. J. and Sánchez, P. (2018). Implications of cohesive strength in asteroid interiors and surfaces and its measurement . Progress in Earth and Planetary Science, 25. Source

BibTeX

@article{scheeres2018implications,
  title = {Implications of cohesive strength in asteroid interiors and surfaces and its measurement},
  author = {Scheeres, Daniel J. and Sánchez, Paul},
  journal = {Progress in Earth and Planetary Science},
  volume = {5},
  number = {25},
  year = {2018},
  doi = {10.1186/s40645-018-0182-9},
  abstract = {Recent observations and theory have indicated that rubble pile asteroids may have a small, but finite, level of tensile strength, allowing them to spin above their spin deformation limit as defined in Holsapple (Icarus 205:430–442, 2010). In Sánchez and Scheeres (Meteorit Planet Sci 49:788–811, 2014), a theory for how such strength could be present in rubble pile asteroids was presented, relying on weak van der Waals forces between fine particulate material in asteroid regolith and in their interiors. The implications of this theory are evaluated and related to the surface strength of regolith and global strength of a rubble pile body. Proposed techniques to measure the strength of regolith using cratering theory are reviewed, as are constraints placed on the global strength of rubble pile asteroids from astronomical observations. Specific examples applied to the Hayabusa2 cratering experiment at its target asteroid are given.}
}

Lorenz, R. D., Turtle, E. P., Barnes, J. W., Trainer, M. G., Adams, D. S., Hibbard, K. E., Sheldon, C. Z., Zacny, K., Peplowski, P. N., Lawrence, D. J., Ravine, M. A., McGee, T. G., Sotzen, K. S., MacKenzie, S. M., Langelaan, J. W., Schmitz, S., Wolfarth, L. S. and Bedini, P. D. (2018). Dragonfly: A Rotorcraft Lander Concept for Scientific Exploration at Titan . Johns Hopkins APL Technical Digest, 3. Source

BibTeX

@article{lorenz2018dragonfly,
  title = {Dragonfly: A Rotorcraft Lander Concept for Scientific Exploration at Titan},
  author = {Lorenz, Ralph D. and Turtle, Elizabeth P. and Barnes, Jason W. and Trainer, Melissa G. and Adams, Douglas S. and Hibbard, Kenneth E. and Sheldon, Colin Z. and Zacny, Kris and Peplowski, Patrick N. and Lawrence, David J. and Ravine, Michael A. and McGee, Timothy G. and Sotzen, Kristin S. and MacKenzie, Shannon M. and Langelaan, Jack W. and Schmitz, Sven and Wolfarth, Larry S. and Bedini, Peter D.},
  journal = {Johns Hopkins APL Technical Digest},
  volume = {34},
  number = {3},
  pages = {374--387},
  year = {2018},
  url = {https://dragonfly.jhuapl.edu/News-and-Resources/docs/34_03-Lorenz.pdf}
}

Milos, F. S. (1997). Galileo Probe Heat Shield Ablation Experiment . Journal of Spacecraft and Rockets, 6. Source

BibTeX

@article{milos1997galileo,
  title = {Galileo Probe Heat Shield Ablation Experiment},
  author = {Milos, Frank S.},
  journal = {Journal of Spacecraft and Rockets},
  volume = {34},
  number = {6},
  pages = {705--713},
  year = {1997},
  doi = {10.2514/2.3293},
  abstract = {Covers advancements in spacecraft and tactical and strategic missile systems, including subsystem design and application, mission design and analysis, materials and structures, developments in space sciences, space processing and manufacturing, space operations, and applications of space technologies to other fields.}
}

Justh, H. L., Dwyer Cianciolo, A. M. and Hoffman, J. (2021). Venus Global Reference Atmospheric Model (Venus-GRAM): User Guide . NASA Marshall Space Flight Center, NASA/TM-20210022168. Source

BibTeX

@techreport{justh2021venus,
  title = {Venus Global Reference Atmospheric Model (Venus-GRAM): User Guide},
  author = {Justh, Hilary L. and Dwyer Cianciolo, Alicia M. and Hoffman, J.},
  number = {NASA/TM-20210022168},
  institution = {NASA Marshall Space Flight Center},
  year = {2021},
  url = {https://ntrs.nasa.gov/citations/20210022168},
  abstract = {This Technical Memorandum (TM) presents the Venus Global Reference Atmospheric Model (Venus-GRAM) and the updated features of the GRAMs. Venus-GRAM is an engineering-oriented atmospheric model that estimates mean values and statistical variations of atmospheric properties for Venus. This TM summarizes the atmospheric data model in Venus-GRAM and provides a guide for the user to obtain, set up, and run the code in various configurations. Additional details regarding the Venus-GRAM input and output files and how to interpret Venus-GRAM results are also provided.}
}

Chen, L.-Y., Neudeck, P. G., Meredith, R. D., Lukco, D., Spry, D. J., Nakley, L. M., Phillips, K. G., Beheim, G. M. and Hunter, G. W. (2018). Sixty Earth-Days Test of a Prototype Pt/HTCC Alumina Package in Simulated Venus Environment . Additional Conferences, 20180006758. Source

BibTeX

@inproceedings{chen2018sixty,
  title = {Sixty Earth-Days Test of a Prototype Pt/HTCC Alumina Package in Simulated Venus Environment},
  author = {Chen, Liang-Yu and Neudeck, Philip G. and Meredith, Roger D. and Lukco, Dorothy and Spry, David J. and Nakley, Leah M. and Phillips, Kyle G. and Beheim, Glenn M. and Hunter, Gary W.},
  booktitle = {Additional Conferences},
  volume = {2018},
  number = {20180006758},
  pages = {000015-000021},
  institution = {NASA},
  address = {Albuquerque, New Mexico},
  year = {2018},
  doi = {10.4071/2380-4491-2018-hiten-0000015},
  abstract = {Abstract This paper presents experimental results of a prototype high temperature co-fired ceramic (HTCC) package with Au/Pt metallization in a three-phase harsh environment test that culminated with 60-day demonstration in simulated Venus surface environment of 465 °C with corrosive atmosphere at 90 bar pressure. The prototype package is based on previously developed and reported HTCC package successfully tested with multiple analog and digital silicon carbide (SiC) high temperatures semiconductor integrated circuits (ICs) at NASA Glenn Research Center in 500 °C Earth air ambient for over ten thousands hours, and short-term tested at temperatures above 800 °C. The three-phase harsh environment test started with 48 hours in 465 °C Earth air, followed by 48 hours in 465 °C nitrogen at 90 bar pressure and 1400 hours in simulated Venus surface environment of 465 °C with corrosive atmosphere at 90 bar. Initial analytical results of the package materials and surfaces after exposure to Venus environment are discussed to assess the stability of the packaging materials in the tested environments. The test in simulated Venus environment was implemented in the NASA Glenn Extreme Environment Rig (GEER). The results of this study suggest that an effective encapsulation of areas of surface metallization and vicinities may help to improve electrical performance of a HTCC alumina packaging system in Venus environment.}
}

Neudeck, P. G., Spry, D. J., Krasowski, M. J., Prokop, N. F., Beheim, G. M., Chen, L.-Y. and Chang, C. W. (2018). Yearlong 500 C Operational Demonstration of Up-scaled 4H-SiC JFET Integrated Circuits . Additional Conferences. Source

BibTeX

@inproceedings{neudeck2018yearlong,
  title = {Yearlong 500 C Operational Demonstration of Up-scaled 4H-SiC JFET Integrated Circuits},
  author = {Neudeck, Philip G. and Spry, David J. and Krasowski, Michael J. and Prokop, Norman F. and Beheim, Glenn M. and Chen, Liang-Yu and Chang, Carl W.},
  booktitle = {Additional Conferences},
  volume = {2018},
  pages = {000071-000078},
  year = {2018},
  doi = {10.4071/2380-4491-2018-hiten-000071},
  abstract = {Abstract This work describes recent progress in the design, processing, and testing of significantly up-scaled 500 °C durable 4H-SiC junction field effect transistor (JFET) integrated circuit (IC) technology with two-level interconnect undergoing development at NASA Glenn Research Center. For the first time, stable electrical operation of semiconductor ICs for over one year at 500 °C in air atmosphere is reported. These groundbreaking durability results were attained on two-level interconnect JFET demonstration ICs with 175 or more transistors on each chip. This corresponds to a more than 7-fold increase in 500 °C-durable circuit complexity from the 24 transistor ring oscillator ICs reported at HiTEC 2016 [1]. These results advance the technology foundation for realizing long-term durable 500 °C ICs with increased functional capability for combustion engine sensing and control, planetary exploration, deep-well drilling monitoring, and other harsh-environment applications.}
}

Heiken, G. H., Vaniman, D. T. and French, B. M. (1991). Lunar Sourcebook: A User's Guide to the Moon . Endeavour. Source

BibTeX

@book{heiken1991lunar,
  title = {Lunar Sourcebook: A User's Guide to the Moon},
  author = {Heiken, Grant H. and Vaniman, David T. and French, Bevan M.},
  journal = {Endeavour},
  volume = {16},
  pages = {96},
  publisher = {Cambridge University Press},
  year = {1991},
  doi = {10.1016/0160-9327(92)90014-g}
}

Hayne, P. O., Bandfield, J. L., Siegler, M. A., Vasavada, A. R., Ghent, R. R., Williams, J.-P., Greenhagen, B. T., Aharonson, O., Elder, C. M., Lucey, P. G. and Paige, D. A. (2017). Global Regolith Thermophysical Properties of the Moon From the Diviner Lunar Radiometer Experiment . Journal of Geophysical Research: Planets, 12. Source

BibTeX

@article{hayne2017global,
  title = {Global Regolith Thermophysical Properties of the Moon From the Diviner Lunar Radiometer Experiment},
  author = {Hayne, Paul O. and Bandfield, Joshua L. and Siegler, Matthew A. and Vasavada, Ashwin R. and Ghent, Rebecca R. and Williams, Jean-Pierre and Greenhagen, Benjamin T. and Aharonson, Oded and Elder, Catherine M. and Lucey, Paul G. and Paige, David A.},
  journal = {Journal of Geophysical Research: Planets},
  volume = {122},
  number = {12},
  pages = {2371--2400},
  year = {2017},
  doi = {10.1002/2017je005387},
  abstract = {Abstract We used infrared data from the Lunar Reconnaissance Orbiter (LRO) Diviner Lunar Radiometer Experiment to globally map thermophysical properties of the Moon's regolith fines layer. Thermal conductivity varies from 7.4 × 10 −4 W m −1 K −1 at the surface to 3.4 × 10 −3 W m −1 K −1 at depths of ~1 m, given density values of 1,100 kg m −3 at the surface to 1,800 kg m −3 at 1 m depth. On average, the scale height of these profiles is ~7 cm, corresponding to a thermal inertia of 55 ± 2 J m −2 K −1 s −1/2 at 273 K, relevant to the diurnally active near‐surface layer, ~4–7 cm. The temperature dependence of thermal conductivity and heat capacity leads to an ~2 times diurnal variation in thermal inertia at the equator. On global scales, the regolith fines are remarkably uniform, implying rapid homogenization by impact gardening of this layer on timescales &lt;1 Gyr. Regional‐ and local‐scale variations show prominent impact features &lt;1 Gyr old, including higher thermal inertia (&gt; 100 J m −2 K −1 s −1/2 ) in the interiors and ejecta of Copernican‐aged impact craters and lower thermal inertia (&lt; 50 J m −2 K −1 s −1/2 ) within the lunar cold spots identified by Bandfield et al. (2014). Observed trends in ejecta thermal inertia provide a potential tool for age dating craters of previously unknown age, complementary to the approach suggested by Ghent et al. (2014). Several anomalous regions are identified in the global 128 pixels per degree maps presented here, including a high‐thermal inertia deposit near the antipode of Tycho crater.}
}

Glaser, P., Oberst, J., Neumann, G. A., Mazarico, E., Speyerer, E. J. and Robinson, M. S. (2017). Illumination Conditions at the Lunar Poles: Implications for Future Exploration . Planetary and Space Science, 20170007365. Source

BibTeX

@article{glaser2017illumination,
  title = {Illumination Conditions at the Lunar Poles: Implications for Future Exploration},
  author = {Glaser, P. and Oberst, J. and Neumann, Gregory A. and Mazarico, Erwan and Speyerer, E. J. and Robinson, Mark S.},
  journal = {Planetary and Space Science},
  volume = {162},
  number = {20170007365},
  pages = {170-178},
  institution = {NASA},
  year = {2017},
  doi = {10.1016/j.pss.2017.07.006},
  abstract = {We produced 400 x 400 km Digital Terrain Models (DTMs) of the lunar poles from Lunar Orbiter Laser Altimeter (LOLA) ranging measurements. To achieve consistent, high-resolution DTMs of 20 m/pixel the individual ranging profiles were adjusted to remove small track-to-track o sets. We used these LOLADTMs to simulate illumination conditions at surface level for 50 x 50 km regions centered on the poles. Illumination was derived in one-hour increments from 01 January, 2017 to 01 January, 2037 to cover the lunar precessional cycle of 18.6 years and to determine illumination conditions over several future mission cycles. We identified three regions receiving high levels of illumination at each pole, e.g. the equator-facing crater rims of Hinshelwood, Peary and Whipple for the north pole and the rim of Shackleton crater, and two locations on a ridge between Shackleton and de Gerlache crater for the south pole. Their average illumination levels range from 69.5% to 82.9%, with the highest illumination levels found at the north pole on the rim of Whipple crater. A more detailed study was carried out for these sites as targets for a lander and/or rover equipped with solar arrays. For this purpose we assumed a lander with a structural height of two meters above the ground (height of the solar panels). Here average illumination levels range from 77.1% to 88.0%, with the maximum found at the ridge between Shackleton and de Gerlache crater on the south pole. Distances, sizes and slopes of nearby Permanently Shadowed Regions (PSRs) as a prime science target were also assessed in this case.}
}

Martínez, G. M., Newman, C. N., De Vicente-Retortillo, A., Fischer, E., Renno, N. O., Richardson, M. I., Fairén, A. G., Genzer, M., Guzewich, S. D., Haberle, R. M., Harri, A.-M., Kemppinen, O., Lemmon, M. T., Smith, M. D., de la Torre-Juárez, M. and Vasavada, A. R. (2017). The Modern Near-Surface Martian Climate: A Review of In-situ Meteorological Data from Viking to Curiosity . Space Science Reviews. Source

BibTeX

@article{martinez2017modern,
  title = {The Modern Near-Surface Martian Climate: A Review of In-situ Meteorological Data from Viking to Curiosity},
  author = {Martínez, G. M. and Newman, C. N. and De Vicente-Retortillo, A. and Fischer, Erik and Renno, N. O. and Richardson, Mark I. and Fairén, A. G. and Genzer, Maria and Guzewich, Scott D. and Haberle, R. M. and Harri, Ari-Matti and Kemppinen, Osku and Lemmon, Mark T. and Smith, Michael D. and de la Torre-Juárez, M. and Vasavada, Ashwin R.},
  journal = {Space Science Reviews},
  volume = {212},
  pages = {295--338},
  year = {2017},
  doi = {10.1007/s11214-017-0360-x},
  abstract = {We analyze the complete set of in-situ meteorological data obtained from the Viking landers in the 1970s to today’s Curiosity rover to review our understanding of the modern near-surface climate of Mars, with focus on the dust, CO 2 and H 2 O cycles and their impact on the radiative and thermodynamic conditions near the surface. In particular, we provide values of the highest confidence possible for atmospheric opacity, atmospheric pressure, near-surface air temperature, ground temperature, near-surface wind speed and direction, and near-surface air relative humidity and water vapor content. Then, we study the diurnal, seasonal and interannual variability of these quantities over a span of more than twenty Martian years. Finally, we propose measurements to improve our understanding of the Martian dust and H 2 O cycles, and discuss the potential for liquid water formation under Mars’ present day conditions and its implications for future Mars missions. Understanding the modern Martian climate is important to determine if Mars could have the conditions to support life and to prepare for future human exploration.}
}

Montabone, L., Forget, F., Millour, E., Wilson, R. J., Lewis, S. R., Cantor, B. A., Kass, D., Kleinböhl, A., Lemmon, M. T., Smith, M. D. and Wolff, M. J. (2015). Eight-year Climatology of Dust Optical Depth on Mars . Icarus. Source

BibTeX

@article{montabone2015eight,
  title = {Eight-year Climatology of Dust Optical Depth on Mars},
  author = {Montabone, L. and Forget, Francois and Millour, Ehouarn and Wilson, R. J. and Lewis, Stephen R. and Cantor, B. A. and Kass, D. and Kleinböhl, A. and Lemmon, Mark T. and Smith, Michael D. and Wolff, M. J.},
  journal = {Icarus},
  volume = {251},
  pages = {65--95},
  year = {2015},
  doi = {10.1016/j.icarus.2014.12.034}
}

Spohn, T., Hudson, T. L., Witte, L., Wippermann, T., Wisniewski, L., Kedziora, B., Vrettos, C., Lorenz, R. D., Golombek, M., Lichtenheldt, R., Grott, M., Knollenberg, J., Krause, C., Fantinati, C., Krueger, T. and Grygorczuk, J. (2022). The InSight-HP3 Mole on Mars: Lessons Learned from Attempts to Penetrate to Depth in the Martian Soil . Advances in Space Research, 8. Source

BibTeX

@article{spohn2022insight,
  title = {The InSight-HP3 Mole on Mars: Lessons Learned from Attempts to Penetrate to Depth in the Martian Soil},
  author = {Spohn, Tilman and Hudson, Troy L. and Witte, Lars and Wippermann, Torben and Wisniewski, Lukasz and Kedziora, Bartosz and Vrettos, Christos and Lorenz, Ralph D. and Golombek, Matthew and Lichtenheldt, Roy and Grott, Matthias and Knollenberg, Joerg and Krause, Christian and Fantinati, Cinzia and Krueger, Torsten and Grygorczuk, Jerzy},
  journal = {Advances in Space Research},
  volume = {69},
  number = {8},
  pages = {3140--3163},
  year = {2022},
  doi = {10.1016/j.asr.2022.02.009},
  abstract = {The NASA InSight lander mission to Mars payload includes the Heat Flow and Physical Properties Package HP3 to measure the surface heat flow. The package was designed to use a small penetrator - nicknamed the mole - to implement a vertical string of temperature sensors in the soil to a depth of 5 m. The mole itself is equipped with sensors to measure a thermal conductivity-depth profile as it proceeds to depth. The heat flow is calculated from the product of the temperature gradient and the thermal conductivity. To avoid the perturbation caused by annual surface temperature variations, the measurements need to be taken at a depth between 3 m and 5 m. The mole is designed to penetrate cohesionless soil similar in rheology to quartz sand which is expected to provide a good analogue material for Martian sand. The sand would provide friction to the buried mole hull to balance the remaining recoil of the mole hammer mechanism that drives the mole forward. Unfortunately, the mole did not penetrate more than 40 cm, roughly a mole length. The failure to penetrate deeper is largely due to a cohesive duricrust of a few tens of centimeter thickness that failed to provide the required friction. Although a suppressor mass and spring as part of the mole hammer mechanism absorb much of the recoil, the available mass did not allow designing a system that fully eliminated the recoil. The mole penetrated to 40 cm depth benefiting from friction provided by springs in the support structure from which it was deployed and from friction and direct support provided by the InSight Instrument Deployment Arm. In addition, the Martian soil provided unexpected levels of penetration resistance that would have motivated designing a more powerful mole. The low weight of the mole support structure was not sufficient to guide the mole penetrating vertically. Roughly doubling the overall mass of the instrument package would have allowed to design a more robust system with little or no recoil, more energy of the mole hammer mechanism and a more massive support structure. In addition, to cope with duricrust a mechanism to support the mole to a depth of about two mole lengths should be considered.}
}

Hassler, D. M. and Norbury, J. W. (2017). Mars Science Laboratory Radiation Assessment Detector (MSL-RAD) Modeling Workshop Proceedings . Life Sciences in Space Research. Source

BibTeX

@article{hassler2017mars,
  title = {Mars Science Laboratory Radiation Assessment Detector (MSL-RAD) Modeling Workshop Proceedings},
  author = {Hassler, Donald M. and Norbury, John W.},
  journal = {Life Sciences in Space Research},
  volume = {14},
  pages = {1-2},
  institution = {NASA},
  year = {2017},
  doi = {10.1016/j.lssr.2017.06.004},
  abstract = {The Radiation Assessment Detector (RAD) (Hassler et al., 2012) onboard the Mars Science Laboratory (MSL) Curiosity rover (Grotzinger et al., 2012) has been making detailed measurements of the radiation environment on the surface of Mars since landing on 6 August 2012 (Hassler et al., 2014; Zeitlin et al., 2016). These measurements are the first of their kind on the surface of another planet and are providing essential measurements of the radiation environment on Mars in preparation for a human mission in the coming decades. The objectives of RAD are; 1) to characterize the energetic particle spectrum on the surface of Mars as a function of time in the solar cycle, including direct (galactic cosmic rays and solar energetic particles) and indirect (neutrons, etc.) radiation created in the atmosphere and regolith, 2) to determine the dose and dose‐equivalent rates as a function of time in the solar cycle, and 3) to use these observations to test and validate space radiation transport models. Initial results of the charged particle spectra (Ehresmann et al., 2014) and neutral particle spectrum (Köhler et al., 2014), as well as dose and dose‐equivalent during cruise (Zeitlin et al., 2013) and on the surface (Hassler et al., 2014) have been reported, and with almost five years of continuous measurements, RAD continues to characterize the radiation environment as solar minimum is approached.}
}

de Groh, K. K. and Banks, B. A. (2019). Atomic Oxygen Erosion Data from the MISSE 2-8 Missions . NASA, 20190025445. Source

BibTeX

@techreport{degroh2019atomic,
  title = {Atomic Oxygen Erosion Data from the MISSE 2-8 Missions},
  author = {de Groh, Kim K. and Banks, Bruce A.},
  number = {20190025445},
  institution = {NASA},
  year = {2019},
  url = {https://ntrs.nasa.gov/citations/20190025445},
  abstract = {Polymers and other oxidizable materials on the exterior of spacecraft in the low Earth orbit (LEO) space environment can be eroded from reaction with atomic oxygen (AO). Therefore, in order to design durable spacecraft it is important to know the extent of erosion that will occur during a mission. This can be determined by knowing the LEO AO erosion yield, E(sub y) (volume loss per incident oxygen atom), of materials susceptible to AO reaction. In addition, recent flight experiments have shown that the AO E(sub y) can vary with the AO fluence and/or solar exposure. Therefore obtaining AO E(sub y) data for materials flown on various spaceflight missions is important. NASA Glenn Research Center has flown numerous experiments as part of the Materials International Space Station Experiment (MISSE) missions on the exterior of the International Space Station to characterize the LEO E(sub y) of polymers, composites, protective coatings, and other spacecraft materials. This report provides a summary of the erosion data for ram samples from six Glenn polymer experiments flown as part of MISSE 2, 4, 6, 7, and 8. A total of 71 types of materials with 111 E(sub y) values are provided. The E(sub y) values for uncoated polymers range from 3.81×10(exp –27) cu cm/atom for DC 93-500 silicone exposed to an AO fluence of 4.62×10(exp 21) atoms/sq cm on MISSE 8 to 9.14×10(exp –24) cu cm/atom for polyoxymethylene (POM) exposed to an AO fluence of 8.43×10(exp 21) atoms/sq cm on MISSE 2. One polymer, Triton oxygen resistant, low modulus (TOR(TM) LM), experienced mass gain when exposed to an AO fluence of 2.15×10(exp 21) atoms/sq cm on MISSE 4. In many cases the same material was flown on numerous missions so that trends for E(sub y) versus AO fluence and/or solar exposure can be determined, along with temperature effects. }
}

DeLombard, R., McPherson, K., Hrovat, K., Moskowitz, M., Rogers, M. J. B. and Reckart, T. (1997). Microgravity Environment Description Handbook . NASA, NASA-TM-107486. Source

BibTeX

@techreport{delombard1997microgravity,
  title = {Microgravity Environment Description Handbook},
  author = {DeLombard, Richard and McPherson, Kevin and Hrovat, Kenneth and Moskowitz, Milton and Rogers, Melissa J. B. and Reckart, Timothy},
  number = {NASA-TM-107486},
  institution = {NASA},
  year = {1997},
  url = {https://ntrs.nasa.gov/citations/19970022250},
  abstract = {The Microgravity Measurement and Analysis Project (MMAP) at the NASA Lewis Research Center (LeRC) manages the Space Acceleration Measurement System (SAMS) and the Orbital Acceleration Research Experiment (OARE) instruments to measure the microgravity environment on orbiting space laboratories. These laboratories include the Spacelab payloads on the shuttle, the SPACEHAB module on the shuttle, the middeck area of the shuttle, and Russia's Mir space station. Experiments are performed in these laboratories to investigate scientific principles in the near-absence of gravity. The microgravity environment desired for most experiments would have zero acceleration across all frequency bands or a true weightless condition. This is not possible due to the nature of spaceflight where there are numerous factors which introduce accelerations to the environment. This handbook presents an overview of the major microgravity environment disturbances of these laboratories. These disturbances are characterized by their source (where known), their magnitude, frequency and duration, and their effect on the microgravity environment. Each disturbance is characterized on a single page for ease in understanding the effect of a particular disturbance. The handbook also contains a brief description of each laboratory.}
}

Robb, C., Pensado, A. R., Winski, R. G., Williams, J. W. and Manwell, M. (2026). Huygens Probe Entry, Descent, and Landing Dynamics Assessment Using a Multi-Body Parachute Model . AIAA SCITECH Forum. Source

BibTeX

@inproceedings{robb2026huygens,
  title = {Huygens Probe Entry, Descent, and Landing Dynamics Assessment Using a Multi-Body Parachute Model},
  author = {Robb, Caleb and Pensado, Alejandro R. and Winski, Richard G. and Williams, James W. and Manwell, Michael},
  booktitle = {AIAA SCITECH Forum},
  year = {2026},
  doi = {10.2514/6.2026-1956},
  abstract = {The Dragonfly project is a New Frontiers Program mission that is slated to launch in 2028 and deliver a rotorcraft to Titan, Saturn’s largest moon. With the launch date approaching, there is an increased focus on the validation and verification of models that are used by the trajectory simulations. One of the models that contributes the most to the uncertainty of the entry, descent, and landing simulation is the atmosphere. Since Huygens is the only mission that has collected in-situ measurements during a descent, a current plan for the validation of the atmosphere model centers around reconciling that flight data with the current atmosphere model used by the Dragonfly flight mechanics team. To complete this, a 6 degree-of-freedom, multi-body simulation has been created using the Program to Optimize Simulated Trajectories 2 (POST2), the prime simulation tool for Dragonfly Entry and Descent, to predict the dynamics of Huygens using the reconciled models. The dynamics predicted by the simulation are then compared to flight data where possible and the previous analysis that was published by the authors last year. Current results show agreement to the available flight data, with an emphasis placed on the metrics that were flagged in the last analysis. The reconciliation is set to continue as areas of concern will be reported and inspected by the model developer.}
}

Walsh, K. J., Ballouz, R.-L., Jawin, E. R., Avdellidou, C., Barnouin, O. S., Bennett, C. A., Bierhaus, E. B., Bos, B. J., Cambioni, S., Connolly, J. H. C., Delbo, M., DellaGiustina, D. N., DeMartini, J., Emery, J. P., Golish, D. R., Haas, P. C., Hergenrother, C. W., Ma, H., Michel, P., Nolan, M. C., Olds, R., Rozitis, B., Richardson, D. C., Rizk, B., Ryan, A. J., Sánchez, P., Scheeres, D. J., Schwartz, S. R., Selznick, S. H., Zhang, Y. and Lauretta, D. S. (2022). Near-zero cohesion and loose packing of Bennu's near subsurface revealed by spacecraft contact . Science Advances, 27. Source

BibTeX

@article{walsh2022near,
  title = {Near-zero cohesion and loose packing of Bennu's near subsurface revealed by spacecraft contact},
  author = {Walsh, Kevin J. and Ballouz, Ronald-Louis and Jawin, Erica R. and Avdellidou, Chrysa and Barnouin, Olivier S. and Bennett, Carina A. and Bierhaus, Edward B. and Bos, Brent J. and Cambioni, Saverio and Connolly, Jr., Harold C. and Delbo, Marco and DellaGiustina, Daniella N. and DeMartini, Joseph and Emery, Joshua P. and Golish, Dathon R. and Haas, Patrick C. and Hergenrother, Carl W. and Ma, Huikang and Michel, Patrick and Nolan, Michael C. and Olds, Ryan and Rozitis, Benjamin and Richardson, Derek C. and Rizk, Bashar and Ryan, Andrew J. and Sánchez, Paul and Scheeres, Daniel J. and Schwartz, Stephen R. and Selznick, Sanford H. and Zhang, Yun and Lauretta, Dante S.},
  journal = {Science Advances},
  volume = {8},
  number = {27},
  pages = {eabm6229},
  year = {2022},
  doi = {10.1126/sciadv.abm6229},
  abstract = {When the OSIRIS-REx spacecraft pressed its sample collection mechanism into the surface of Bennu, it provided a direct test of the poorly understood near-subsurface physical properties of rubble-pile asteroids, which consist of rock fragments at rest in microgravity. Here, we find that the forces measured by the spacecraft are best modeled as a granular bed with near-zero cohesion that is half as dense as the bulk asteroid. The low gravity of a small rubble-pile asteroid such as Bennu effectively weakens its near subsurface by not compressing the upper layers, thereby minimizing the influence of interparticle cohesion on surface geology. The underdensity and weak near subsurface should be global properties of Bennu and not localized to the contact point.}
}

Lauretta, D. S., Hergenrother, C. W., Chesley, S. R., Leonard, J. M., Pelgrift, J. Y., Adam, C. D., Al Asad, M., Antreasian, P. G., Ballouz, R.-L., Becker, K. J., Bennett, C. A., Bos, B. J., Bottke, W. F., Brozović, M., Campins, H., Connolly, J. H. C., Daly, M. G., Davis, A. B., de León, J., DellaGiustina, D. N., Drouet d'Aubigny, C. Y., Dworkin, J. P., Emery, J. P., Farnocchia, D., Glavin, D. P., Golish, D. R., Hartzell, C. M., Jacobson, R. A., Jawin, E. R., Jenniskens, P., Kidd, J. J. N., Lessac-Chenen, E. J., Li, J.-Y., Libourel, G., Licandro, J., Liounis, A. J., Maleszewski, C. K., Manzoni, C., May, B., McCarthy, L. K., McMahon, J. W., Michel, P., Molaro, J. L., Moreau, M. C., Nelson, D. S., Owen, J. W. M., Rizk, B., Roper, H. L., Rozitis, B., Sahr, E. M., Scheeres, D. J., Seabrook, J. A., Selznick, S. H., Takahashi, Y., Thuillet, F., Tricarico, P., Vokrouhlický, D. and Wolner, C. W. (2019). Episodes of particle ejection from the surface of the active asteroid (101955) Bennu . Science, eaay3544. Source

BibTeX

@article{lauretta2019episodes,
  title = {Episodes of particle ejection from the surface of the active asteroid (101955) Bennu},
  author = {Lauretta, Dante S. and Hergenrother, Carl W. and Chesley, Steven R. and Leonard, Jason M. and Pelgrift, John Y. and Adam, Coralie D. and Al Asad, M. and Antreasian, Peter G. and Ballouz, Ronald-Louis and Becker, Kris J. and Bennett, Carina A. and Bos, Brent J. and Bottke, W. F. and Brozović, M. and Campins, H. and Connolly, Jr., H. C. and Daly, Michael G. and Davis, A. B. and de León, J. and DellaGiustina, Daniella N. and Drouet d'Aubigny, C. Y. and Dworkin, Jason P. and Emery, J. P. and Farnocchia, Davide and Glavin, Daniel P. and Golish, Dathon R. and Hartzell, C. M. and Jacobson, R. A. and Jawin, Erica R. and Jenniskens, P. and Kidd, Jr., J. N. and Lessac-Chenen, E. J. and Li, J.-Y. and Libourel, Guy and Licandro, J. and Liounis, Andrew J. and Maleszewski, C. K. and Manzoni, C. and May, B. and McCarthy, L. K. and McMahon, J. W. and Michel, Patrick and Molaro, J. L. and Moreau, Michael C. and Nelson, Derek S. and Owen, Jr., W. M. and Rizk, Bashar and Roper, Heather L. and Rozitis, Benjamin and Sahr, E. M. and Scheeres, Daniel J. and Seabrook, J. A. and Selznick, Sanford H. and Takahashi, Y. and Thuillet, Florian and Tricarico, P. and Vokrouhlický, D. and Wolner, Catherine W.V.},
  journal = {Science},
  volume = {366},
  number = {eaay3544},
  year = {2019},
  doi = {10.1126/science.aay3544},
  abstract = {Bennu ejects material from its surface Most asteroids appear inert, but remote observations show that a small number experience mass loss from their surfaces. Lauretta and Hergenrother et al. describe close-range observations of mass loss on the near-Earth asteroid Bennu (see the Perspective by Agarwal). Shortly after arriving at Bennu, navigation cameras on the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security—Regolith Explorer) spacecraft detected objects 1 to 10 centimeters in diameter moving above the surface. Analysis of the objects' trajectories showed that they originated in discrete ejection events from otherwise unremarkable locations on Bennu. Some objects remained in orbit for several days, whereas others escaped into interplanetary space. The authors suggest multiple plausible mechanisms that could underlie this activity. Science , this issue p. eaay3544 ; see also p. 1192}
}

Kremic, T., Vento, D., Lalli, N. and Palinski, T. (2014). Extreme Environment Simulation - Current and New Capabilities to Simulate Venus and Other Planetary Bodies . IEEE Aerospace Conference, 20140013390. Source

BibTeX

@inproceedings{kremic2014extreme,
  title = {Extreme Environment Simulation - Current and New Capabilities to Simulate Venus and Other Planetary Bodies},
  author = {Kremic, Tibor and Vento, Dan and Lalli, Nick and Palinski, Timothy},
  booktitle = {IEEE Aerospace Conference},
  number = {20140013390},
  pages = {1-9},
  institution = {NASA},
  year = {2014},
  doi = {10.1109/aero.2014.6836350},
  abstract = {Science, technology, and planetary mission communities have a growing interest in components and systems that are capable of working in extreme (high) temperature and pressure conditions. Terrestrial applications range from scientific research, aerospace, defense, automotive systems, energy storage and power distribution, deep mining and others. As the target environments get increasingly extreme, capabilities to develop and test the sensors and systems designed to operate in such environments will be required. An application of particular importance to the planetary science community is the ability for a robotic lander to survive on the Venus surface where pressures are nearly 100 times that of Earth and temperatures approach 500C. The scientific importance and relevance of Venus missions are stated in the current Planetary Decadal Survey. Further, several missions to Venus were proposed in the most recent Discovery call. Despite this interest, the ability to accurately simulate Venus conditions at a scale that can test and validate instruments and spacecraft systems and accurately simulate the Venus atmosphere has been lacking. This paper discusses and compares the capabilities that are known to exist within and outside the United States to simulate the extreme environmental conditions found in terrestrial or planetary surfaces including the Venus atmosphere and surface. The paper then focuses on discussing the recent additional capability found in the NASA Glenn Extreme Environment Rig (GEER). The GEER, located at the NASA Glenn Research Center in Cleveland, Ohio, is designed to simulate not only the temperature and pressure extremes described, but can also accurately reproduce the atmospheric compositions of bodies in the solar system including those with acidic and hazardous elements. GEER capabilities and characteristics are described along with operational considerations relevant to potential users. The paper presents initial operating results and concludes with a sampling of investigations or tests that have been requested or expected.}
}

Neudeck, P. G., Spry, D. J., Krasowski, M. J., Chen, L., Greer, L. C., Chang, C. W., Lukco, D., Beheim, G. M. and Prokop, N. F. (2021). Upscaling of 500 C Durable SiC JFET-R Integrated Circuits . International Conference and Exhibition on High Temperature Electronics. Source

BibTeX

@inproceedings{neudeck2021upscaling,
  title = {Upscaling of 500 C Durable SiC JFET-R Integrated Circuits},
  author = {Neudeck, Philip G. and Spry, David J. and Krasowski, Michael J. and Chen, Liangyu and Greer, Lawrence C. and Chang, Carl W. and Lukco, Dorothy and Beheim, Glenn M. and Prokop, Norman F.},
  booktitle = {International Conference and Exhibition on High Temperature Electronics},
  volume = {2021},
  pages = {000064-000068},
  year = {2021},
  doi = {10.4071/2380-4491.2021.hitec.000064},
  abstract = {Abstract At HiTEC 2018, NASA Glenn Research Center reported the first demonstration of yearlong 500 °C operation of ceramic-packaged “Generation 10” ~200-transistor integrated circuits (ICs) based on two-level interconnect silicon carbide (4H-SiC) junction field effect transistors and resistors (JFET-R). This HiTEC 2021 submission updates on-going efforts at NASA Glenn spanning two subsequent prototype IC generations “11 and 12” to increase both complexity and durability of these ICs. Increased chip complexities of around 1000 transistors/chip for Gen. 11 and near 3000 transistors/chip for Gen. 12 are made possible by reductions in minimum layout feature sizes (including resistor width shrinkage from 6 μm to 2 μm) coupled with enlarged die size (from 3 × 3 mm to 5 × 5 mm). Gen. 11 ICs electrically tested to date include an 8-bit delta-sigma analog to digital converter (ADC) as well as upscaled random access memory (RAM) and nearly 1 kbit read only memory (ROM). However, Gen. 11 prototype ICs exhibited significantly lower yield and durability than Gen. 10 ICs. Development of revised processing is being investigated towards mitigating these issues in subsequent Gen. 12 fabrication run currently in progress.}
}

Beckley, B. W., Motil, C. A., Henry, I. M., Chi, I. S. and Sprouse, M. D. (2024). Glenn Extreme Environments Rig (GEER) Facility Users Guide . Planetary Science Technology Symposium, 20240012869. Source

BibTeX

@inproceedings{beckley2024glenn,
  title = {Glenn Extreme Environments Rig (GEER) Facility Users Guide},
  author = {Beckley, Blake W. and Motil, Craig A. and Henry, Ian M. and Chi, Ike S. and Sprouse, Mark D.},
  booktitle = {Planetary Science Technology Symposium},
  number = {20240012869},
  institution = {NASA},
  address = {Cleveland, OH},
  year = {2024},
  url = {https://ntrs.nasa.gov/citations/20240012869},
  abstract = {The Glenn Extreme Environment Rig (GEER) is a large capacity pressure vessel capable of simulating high pressure and temperature conditions with a specified, custom mixture of gas. The chamber is certified for operation in physical and chemical conditions representative of the surface conditions of Venus. It can accommodate large scientific or engineering test articles while maintaining the specified conditions indefinitely. The user-configurable gas supply is capable of handling a mixture of up to nine independent streams for injection directly into the vessel. GEER is supported in part by NASA’s Planetary Science Division under the Science Mission Directorate and is available for use by the commercial, academic, and research communities.

GEER was operationally commissioned in November of 2014. At that time, it successfully maintained the temperature, pressure, and chemistry of the Venus surface atmosphere. In the spring of 2015, GEER began operations for engineering and scientific research. Since then, over 20 tests have been successfully conducted in the chamber with a variety of atmospheric test conditions.}
}

Justus, C. G., Duvall, A. and Keller, V. W. (2003). Engineering-Level Model Atmospheres for Titan and Neptune . AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, 20030066242. Source

BibTeX

@inproceedings{justus2003engineering,
  title = {Engineering-Level Model Atmospheres for Titan and Neptune},
  author = {Justus, C. G. and Duvall, Aleta and Keller, Vernon W.},
  booktitle = {AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit},
  number = {20030066242},
  institution = {NASA Marshall Space Flight Center},
  year = {2003},
  doi = {10.2514/6.2003-4803},
  abstract = {Engineering-level atmospheric models for Titan and Neptune have been developed for use in NASA s systems analysis studies of aerocapture applications in missions to the outer planets. Analogous to highly successful Global Reference Atmospheric Models for Earth (GRAM, Justus et al., 2000) and Mars (Mars-GRAM, Justus and Johnson, 2001, Justus et al., 2002) the new models are called Titan-GRAM and Neptune-GRAM. Like GRAM and Mars-GRAM, an important feature of Titan-GRAM and Neptune-GRAM is their ability to simulate quasi-random perturbations for Monte- Carlo analyses in developing guidance, navigation and control algorithms, and for thermal systems design.}
}