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This presentation contains photographs of the integration of the Gunsmoke-J Flight Unit 4 satellite at the VOX Space, Inc., facility located in Long Beach California. The photographs were taken on April 29, 2021. VOX Space has granted their approval for release if LANL and the DoD sponsor also concur.
This report provides a list of accomplishments of the Mars 2020 Risk Integration and Uncertainty Working Group for the fiscal year 2017 which includes participation in the Technical Information Meeting #2, review and comments on the methodologies and results provided in the Mars 2020 Safety Analysis Report (SAR) Draft Databook, development of a Probabilistic Risk Assessment model in the risk assessment program SAPHIRE using the data provided in the SAR Databook, and an independent launch risk analysis based on the Mars 2020 launch vehicle’s lineage and design similarity to other launch vehicles.
The Super Strypi Navigation, Guidance & Control Software is a real-time implementation of the navigation, guidance and control algorithms designed to deliver a payload to a desired orbit for the rail launched Super Strypi launch vehicle. The software contains all flight control algorithms required from pre-launch until orbital insertion. The flight sequencer module calls the NG&C functions at the appropriate times of flight. Additional functionality includes all the low level drivers and I/O for communicating to other systems within the launch vehicle and to the ground support equipment. The software is designed such that changes to the launch location and desired orbit can be changed without recompiling the code.
Since the early 1960’s the Department of Energy (DOE) and its predecessor agencies have provided radioisotope power systems (RPS) to NASA as an enabling technology for deep space and various planetary missions. They provide reliable power in situations where solar and/or battery power sources are either untenable or would place an undue mass burden on the mission. In the modern era of the past twenty years there has been no time that multiple missions have been considered for launching from Kennedy Space Center (KSC) during the same year. The closest proximity of missions that involved radioisotope power systems would be that of Galileo (October 1989) and Ulysses (October 1990). The closest that involved radioisotope heater units would be the small rovers Spirit and Opportunity (May and July 2003) used in the Mars Exploration Rovers (MER) mission. It can be argued that the rovers sent to Mars in 2003 were essentially a special case since they staged in the same facility and used a pair of small launch vehicles (Delta II). This paper examines constraints on the frequency of use of radioisotope power systems with regard to launching them from Kennedy Space Center using currently available launch vehicles. This knowledge may be useful as NASA plans for its future deep space or planetary missions where radioisotope power systems are used as an enabling technology. Previous descriptions have focused on single mission chronologies and not analyzed the timelines with an emphasis on multiple missions.
Resolve is a high-resolution X-ray spectrometer onboard the X-Ray Imaging and Spectroscopy Mission (XRISM), launched on September 6 (UT), 2023. The Resolve has performed better than its required spectral resolution (7 eV at full width at half maximum at 6 keV), both on the ground and in orbit, and has been confirmed to have comparable performance to the soft X-ray spectrometer onboard the ASTRO-H (Hitomi) satellite. The focal plane is composed of an array of microcalorimeter detectors operated at 50 mK to achieve the required energy resolution, and the cooling system is designed to satisfy the lifetime requirement of over 3 years. The focal plane and cooling system are contained in a vacuum-insulated dewar. The cooling system is equipped with a two-stage adiabatic demagnetization refrigerator (ADR) that uses superfluid liquid helium (LHe) as its heat sink. The system includes a third ADR stage that can be used to provide the heat sink when the helium is exhausted. A Joule–Thomson cooler and several two-stage Stirling coolers are used to reduce the heat load on the LHe. During pre-launch operations, we carried out a superfluid LHe top-off operation. The resultant amount of LHe onboard Resolve was over 35 L before launch, which is sufficient to meet the lifetime requirement. During post-launch operation, the LHe vent valve was opened 5 min after launch during rocket acceleration, and the cryocoolers were turned on after several orbits, as planned, which established stable cooling within the dewar. Pre- and post-launch operations for the Resolve instrument were planned around multiple constraints from launch vehicle operations; all were successfully completed, and the launch requirements were fully met.
Historically space reactors flown or designed for the U.S. and Russia used Highly Enriched Uranium (HEU) for fuel. HEU almost always produces a small and lighter reactor. Since mass increases launch costs or decreases science payloads, HEU was the natural choice. However in today’s environment, the proliferation of HEU has become a major concern for the U.S. government and hence a policy issue. In addition, launch costs are being reduced as the space community moves toward commercial launch vehicles. HEU also carries a heavy security cost to process, test, transport and launch. Together these issues have called for a re-investigation into space reactors the use Low Enriched Uranium (LEU) fuel.
This project is in support of our national goal to reduce our dependence on fossil fuels. By supporting efforts that contribute toward the successful mass production of plug-in hybrid electric vehicles, our nation’s transportation-related fuel consumption can be offset with energy from the grid. Over four and a half years ago, when this project was originally initiated, plug-in electric vehicles were not readily available in the mass marketplace. Through the creation of a 21 unit plug-in hybrid vehicle fleet, this program was designed to demonstrate the feasibility of the technology and to help build cross-industry familiarity with the technology and interface of this technology with the grid. Ford Escape PHEV Demonstration Fleet 3 March 26, 2014 Since then, however, plug-in vehicles have become increasingly more commonplace in the market. Ford, itself, now offers an all-electric vehicle and two plug-in hybrid vehicles in North America and has announced a third plug-in vehicle offering for Europe. Lessons learned from this project have helped in these production vehicle launches and are mentioned throughout this report. While the technology of plugging in a vehicle to charge a high voltage battery with energy from the grid is now in production, the ability for vehicle-to-grid or bi-directional energy flow was farther away than originally expected. Several technical, regulatory and potential safety issues prevented progressing the vehicle-to-grid energy flow (V2G) demonstration and, after a review with the DOE, V2G was removed from this demonstration project. Also proving challenging were communications between a plug-in vehicle and the grid or smart meter. While this project successfully demonstrated the vehicle to smart meter interface, cross-industry and regulatory work is still needed to define the vehicle-to-grid communication interface.
Near-Earth asteroid 2024 YR 4 was discovered on 2024-12-27 and its probability of Earth impact in December 2032 peaked at ~3% on 2025-02-18. Additional observations ruled out Earth impact by 2025-02-23. However, the probability of lunar impact in December 2032 then rose, reaching ~4% by the end of the apparition in May 2025. James Webb Space Telescope (JWST) observations on 2025-03-26 estimated the asteroid’s diameter at 60 ± 7 m. Studies of 2024 YR 4 ’s potential lunar impact effects suggest lunar ejecta could increase micrometeoroid debris flux in low Earth orbit up to 1000 times above background levels over just a few days, possibly threatening astronauts and spacecraft. In this work, we present options for space missions to 2024 YR 4 that could be utilized if lunar impact is confirmed. Here, we cover flyby & rendezvous reconnaissance, deflection, and robust disruption of the asteroid. We examine both rapid-response and delayed launch options through 2032. We evaluate chemical and solar electric propulsion, various launch vehicles, optimized deep space maneuvers, and gravity assists. Re-tasking extant spacecraft and using built spacecraft not yet launched are also considered. The best reconnaissance mission options launch in late 2028, leaving only approximately three years for development at the time of this writing in August 2025. Deflection missions were assessed and appear impractical. However, kinetic robust disruption missions are available with launches between April 2030 and April 2032. Nuclear robust disruption missions are also available with launches between late 2029 and late 2031. Finally, even if lunar impact is ruled out there is significant potential utility in deploying a reconnaissance mission to characterize the asteroid.
Vehicles equipped with idle-stop (IS) systems are capable of engine shut down when the vehicle is stopped and rapid engine re-start for the vehicle launch. This capability reduces fuel consumption and emissions during periods when the engine is not being utilized to provide propulsion or to power accessories. IS systems are a low-cost and fast-growing technology in the industry-wide pursuit of increased vehicle efficiency, possibly becoming standard features in European vehicles in the near future. In contrast, currently there are only three non-hybrid vehicle models for sale in North America with IS systems and these models are distinctly low-volume models. As part of the United States Department of Energy’s Advanced Vehicle Testing Activity, ECOtality North America has tested the real-world effect of IS systems on fuel consumption in three vehicle models imported from Europe. These vehicles were chosen to represent three types of systems: (1) spark ignition with 12-V belt alternator starter; (2) compression ignition with 12-V belt alternator starter; and (3) direct-injection spark ignition, with 12-V belt alternator starter/combustion restart. The vehicles have undergone both dynamometer and on-road testing; the test results show somewhat conflicting data. The laboratory data and the portion of the on-road data in which driving is conducted on a prescribed route with trained drivers produced significant fuel economy improvement. However, the fleet data do not corroborate improvement, even though the data show significant engine-off time. It is possible that the effects of the varying driving styles and routes in the fleet testing overshadowed the fuel economy improvements. More testing with the same driver over routes that are similar with the IS system-enabled and disabled is recommended. There is anecdotal evidence that current Environmental Protection Agency fuel economy test procedures do not capture the fuel economy gains that IS systems produce in real-world driving. The program test results provide information on the veracity of these claims.
It is apparent the cost of planetary exploration is rising as mission budgets declining. Currently small scientific beds geared to performing limited tasks are being developed and launched into low earth orbit (LEO) in the form of small-scale satellite units, i.e., CubeSats. These micro- and nano-satellites are gaining popularity among the university and science communities due to their relatively low cost and design flexibility. To date these small units have been limited to performing tasks in LEO utilizing solar-based power. If a reasonable propulsion system could be developed, these CubeSat platforms could perform exploration of various extra-terrestrial bodies within the solar system engaging a broader range of researchers. Additionally, being mindful of mass, smaller cheaper launch vehicles (~1,000 kgs to LEO) can be targeted. This, in effect, allows for beneficial exploration to be conducted within limited budgets. Researchers at the Center for Space Nuclear Re-search (CSNR) are proposing a low mass, radioisotope-based, dual-mode propulsion system capable of extending the exploration realm of these CubeSats out of LEO. The proposed radioisotope-based system would leverage the high specific energies [J/kg] associated with radioisotope materials and enhance their inherent low specific powers [W/g]. This is accomplished by accumulating thermal energy from nuclear decay within a central core over time. This allows for significant amounts of power to be transferred to a flowing gas over short periods of time. In the proposed configuration the stored energy can be utilized in two ways: (1) with direct propellant injection to the core, the energy can be converted into thrust through the use of a converging-diverging nozzle and (2) by flowing a working fluid through the core and subsequent Brayton engine, energy within the core can be converted to electrical energy. The first scenario achieves moderate ranges of thrust, but at a higher Isp than traditional chemical-based systems. The second scenario allows for the production of electrical power, which is then available for electric-based propulsion. Additionally, once at location the production of electrical power can be dedicated to the payload’s communication system for data transfer. Ultimately, the proposed dual-mode propulsion platform capitalizes on the benefits of two types of propulsion methods – the thrust of thermal propulsion ideal for quick orbital maneuvers and the specific impulse of electric propulsion ideal for efficient inter-planetary travel. Previous versions of this RTR-based concept have been studied for various applications [NETS 1-3]. The current version of this concept is being matured through a NASA Innovative Advanced Concepts (NIAC) Phase I grant, awarded for FY 2014. In this study the RTR concept is being developed to deliver a 6U CubeSat payload to the orbit of the Saturnian moon - Enceladus. Additionally, this study will develop an entire mission architecture for Enceladus targeting a total allowable launch mass of 1,000 kg.
Space launch vehicles and strategic military vehicles commonly employ composite solid rocket propellants containing Fe{sub 2}O{sub 3} as ballistic modifier. Nanoscale catalysts, including nanoscale Fe{sub 2}O{sub 3}, have been reported to exhibit superior activity in the thermal decomposition and combustion of composite rocket propellants. However, scalable methods to prepare such nano-structured catalysts with high performance as ballistic modifiers and systematic studies relating the synthesis parameters to the catalyst characteristics and consequently to the thermal and combustion properties of the composite propellant are scarce. In this paper, we report a novel and facile route to prepare nano-structured Fe{sub 2}O{sub 3} with enhanced catalytic activity in the ballistic modification of ammonium perchlorate (AP)-based composite solid rocket propellant. A submerged spray precipitation method using air-assisted liquid-centered coaxial atomization has been developed to prepare these nano-structured Fe{sub 2}O{sub 3} catalysts. The prepared Fe{sub 2}O{sub 3} catalysts possess higher surface area and exhibit superior activity in the thermal sensitization of AP, leading to an 88% increase in the burning rate of AP-based composite solid rocket propellants, than the Fe{sub 2}O{sub 3} catalyst prepared via traditional precipitation method. Merits of the developed preparatory route, influence of the atomization process on the nano-structure morphology and subsequent benefits of these nano-structured catalysts on the ballistic properties of AP-based propellants are demonstrated and discussed in this paper.
Astrophysics Telescope for Large Area Spectroscopy Probe is a concept for a National Aeronautics and Space Administration probe-class space mission that will achieve ground-breaking science in the fields of galaxy evolution, cosmology, Milky Way, and the Solar System. It is the follow-up space mission to Wide Field Infrared Survey Telescope (WFIRST), boosting its scientific return by obtaining deep 1–4 μm slit spectroscopy for ~70% of all galaxies imaged by the ~2 000 deg 2 WFIRST High Latitude Survey at z > 0.5. Astrophysics Telescope for Large Area Spectroscopy will measure accurate and precise redshifts for ~200 M galaxies out to z < 7, and deliver spectra that enable a wide range of diagnostic studies of the physical properties of galaxies over most of cosmic history. Astrophysics Telescope for Large Area Spectroscopy Probe and WFIRST together will produce a 3D map of the Universe over 2 000 deg 2 , the definitive data sets for studying galaxy evolution, probing dark matter, dark energy and modifications of General Relativity, and quantifying the 3D structure and stellar content of the Milky Way. Astrophysics Telescope for Large Area Spectroscopy Probe science spans four broad categories: (1) Revolutionising galaxy evolution studies by tracing the relation between galaxies and dark matter from galaxy groups to cosmic voids and filaments, from the epoch of reionisation through the peak era of galaxy assembly; (2) Opening a new window into the dark Universe by weighing the dark matter filaments using 3D weak lensing with spectroscopic redshifts, and obtaining definitive measurements of dark energy and modification of General Relativity using galaxy clustering; (3) Probing the Milky Way’s dust-enshrouded regions, reaching the far side of our Galaxy; and (4) Exploring the formation history of the outer Solar System by characterising Kuiper Belt Objects. Astrophysics Telescope for Large Area Spectroscopy Probe is a 1.5 m telescope with a field of view of 0.4 deg 2 , and uses digital micro-mirror devices as slit selectors. It has a spectroscopic resolution of R = 1 000, and a wavelength range of 1–4 μm. The lack of slit spectroscopy from space over a wide field of view is the obvious gap in current and planned future space missions; Astrophysics Telescope for Large Area Spectroscopy fills this big gap with an unprecedented spectroscopic capability based on digital micro-mirror devices (with an estimated spectroscopic multiplex factor greater than 5 000). Astrophysics Telescope for Large Area Spectroscopy is designed to fit within the National Aeronautics and Space Administration probe-class space mission cost envelope; it has a single instrument, a telescope aperture that allows for a lighter launch vehicle, and mature technology (we have identified a path for digital micro-mirror devices to reach Technology Readiness Level 6 within 2 yr). In conclusion, Astrophysics Telescope for Large Area Spectroscopy Probe will lead to transformative science over the entire range of astrophysics: from galaxy evolution to the dark Universe, from Solar System objects to the dusty regions of the Milky Way
Cyanate ester (CE) is an important class of materials among high-temperature performance thermosets. It is used in aerospace launch vehicles, heat sinks, booms, and trusses of satellites etc. due to its high glass transition temperatures (>220°C), excellent thermal stability, and low flammability. Current approaches to improve the thermal stability of CE include incorporation of siloxanes or phosphorus- based flame retardants (PFRs). In this work, we have explored boron-based hydroxy (PD) and epoxy (EP) functionalized carborane additives to improve the thermal properties of CE. Carborane fillers were solvent blended at various mass loadings in the resin and cured to study their effect on thermal properties. PD and EP carboranes react with CE to form iminocarbonate and oxazolidinone linkages respectively. Cure kinetics studies at different wt% loadings explained that carboranes catalyze the curing reaction by reducing curing activation energy by about 54% and 26% for 10 wt% loadings of PD and EP carboranes respectively. In addition, carborane-filled cyanate ester (CE) nanocomposites demonstrate an exceptionally high thermal stability as compared to the pristine resin in air and inert environment. Our thermogravimetric analysis (TGA) experiments show that the ultimate char yield of the resin can be increased from 0% to as high as 76% and 82% with 30 wt% PD and EP carborane loading respectively at 1000 °C in air. The initial degradation temperature T d;5 of the composites decreased with increasing carborane loadings in both air and argon. For instance, T d;5 for CE was 465 and 471.6 °C in argon and air while that for P20 was 437.4 and 452.1 °C. Modulated TGA studies gave evidence of the effect of carboranes on degradation kinetics and the mechanism of the resin in air and inert environment. The effect of bonding between carboranes and CE at various loadings on the thermal expansion of the matrix was also studied using Thermomechanical Analyzer (TMA). PD carborane reduced the T g for P20 to about 225 °C while CE had T g >350 °C.
Cryogenic insulation designed to operate at various pressures from one atmosphere to vacuum, with high thermal performance and light weight, is needed for cryogenically fueled space launch vehicles and aircraft. Multilayer insulation (MLI) performs well in a high vacuum, but the required vacuum shell for use in the atmosphere is heavy. Spray-on foam insulation (SOFI) is often used in these systems because of its light weight, but can have a higher heat flux than desired. We report on the continued development of Load Responsive Multilayer Insulation (LRMLI), an advanced thermal insulation system that uses dynamic beam discrete spacers that provide high thermal performance both in atmosphere and vacuum. LRMLI consists of layers of thermal radiation barriers separated and supported by micromolded polymer spacers. The spacers have low thermal conductance, and self-support a thin, lightweight vacuum shell that provides internal high vacuum in the insulation. The dynamic load responsive spacers compress to support the external load of a vacuum shell in one atmosphere, and decompress under reduced atmospheric pressure for lower heat leak. Structural load testing was performed on the spacers with various configurations. LRMLI was installed on a 400 liter tank and boil off testing with liquid nitrogen performed at various chamber pressures from one atmosphere to high vacuum. Testing was also performed with an MLI blanket on the outside of the LRMLI.
A comprehensive modal survey test based on multi-input multi-output experimental modal analysis techniques was conducted on the flight model of the CASSIOPE spacecraft in the final stages of integration, which included all of the payload and bus instruments and electronics boxes. The multiple-input excitation for the spacecraft was generated using two portable electrodynamic modal shakers installed on the top and bottom of the spacecraft to distribute the excitation energy and the response was measured using 81 miniature accelerometers. Advanced modal analysis software was used to extract modal parameters from the measured data and critical modes were compared with predictions from the finite element model. Most modes identified through the experimental data compared favorably with the predictions. Nevertheless, some differences were large enough to require iterative update of the finite element model. The structural dynamics information from the updated finite element model was used to plan the mechanical vibration qualification test and predict the response of the spacecraft to the launch vehicle environmental loads through coupled loads analysis to provide confidence in the structural integrity of the spacecraft design. This paper describes the details of the methodology used to perform the successful experimental modal test to efficiently extract the critical modes of the spacecraft to correlate with the model.
SAND2024-09978O The Launch Accident Sequence Evaluation Program is used to calculate the source term for the consequence analysis involving a launch vehicle accident with a space nuclear system. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.
Safely launching and landing spacecraft, especially reusable spacecraft, requires detailed inspections of the launch vehicle to identify potential manufacturing and service-induced flaws. As an automated full-structure ultrasonic scanning technology, Acoustic Steady-State Excitation Spatial Spectroscopy (ASSESS) can rapidly and non-intrusively detect a wide variety of defects in applications where identifying subtle flaws is paramount. ASSESS is a non-destructive evaluation technology that leverages continuous excitation and laser Doppler vibrometry to make fast, high-quality inspections at stand-off distances. The ASSESS technology has undergone extensive laboratory testing and several field tests specific to oil and gas and additive manufacturing applications. We seek a commercialization partner to fund aerospace application-specific R&D and product development through a Cooperative Research and Development Agreement (CRADA).
Mechanical shocks, particularly pyroshocks, are environments that all spacecraft and launch vehicles experience. Pyroshocks can be challenging design environments for space hardware because these events are often high frequency, high intensity transients. Furthermore, since design decisions must be made relatively early in the design phase, understanding, and accurately defining pyroshock excitation and the loads that it imparts on components is important to ensure the high reliability required of spacecraft and rockets. Here, general guidelines about shock transmission through spacecraft structures are provided in NASA and MIL handbooks and standards, but these are relatively broad guidelines, and recent studies have shown that more accurate and less-conservative predictions are needed. However, predicting shock response accurately is still a challenge because of the high frequencies in a pyroshock excitation.