Earth Orbit Environment Research Articles

Strong and flexible MXene-based nanocomposite films for atomic oxygen resistance and electromagnetic interference shielding

MXene has garnered considerable attention as a promising candidate for multifunctional artificial materials, owing to its exceptional mechanical performance and superior electric conductivity. However, macroscopically layered films assembled by MXene nanosheets are usually accompanied by serious degradation of mechanical properties. Moreover, there is a notable paucity of investigations on MXene in low Earth orbit (LEO) environment. Inspired by the layered structure of nacre, we applied polyurethane (PU) as an interfacial crosslinking agent to improve the mechanical properties of MXene films. The optimized MXene/PU (MP) nanocomposite film exhibited a tensile strength of 298.02 MPa and a toughness of 13.81 MJ m−3, surpassing those of the pure MXene film by 260 % and 1300 %, respectively. The atomic oxygen (AO) erosion yield of MP was approximately one order of magnitude lower than that of commercial Kapton films, which was attributed to the shielding effect of MXene against AO attacks. Remarkably, the MP nanocomposite film demonstrated exceptional retention of tensile strength under various extreme conditions including AO irradiation, cryogenic-high temperature, cyclic thermal shock and hot water. Contributed by multi-layer structural design and high conductivity, the MP exhibited a high electromagnetic interference shielding effectiveness (EMI SE) of 48 dB and a specific SE divided by thickness (SSE/t) of 13,479 dB cm2 g−1 at the thickness of 20 μm. Consequently, the nacre-like MP nanocomposite film with exceptional mechanical properties and high-level functional performance holds substantial promise as a multifunctional space material for LEO environments.

SPHEREx payload thermal architecture and analysis

The SPHEREx (Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer) is an all-sky spectral survey in a Sun-synchronous low earth orbit. It measures spectrum in the near infrared band from 0.75 µm to 5 µm. To achieve this wavelength coverage, the instrument has two focal plane arrays, both passively cooled at <55 K (mid-wave infrared) and <80 K (short-wave infrared). Additionally, the instrument requires no moving parts for spectral resolution, relying instead on spacecraft-controlled pointing. A thermally isolating structure and a set of V-groove radiators reduce the heat flow conducted and radiated from the spacecraft bus. The thermal system also blocks the incident solar flux and earth radiation from reaching the sensitive cryogenic instrument while still allowing substantial pointing flexibility. The combination of passive cryogenic cooling and survey requirements in a sun exposed low earth orbit environment presents a challenge for the thermal design. This paper will discuss the SPHEREx payload overall thermal architecture, bounding thermal environments, the component thermal design, and analysis of on-flight performance.

Mission analysis and guidance and control for the SpEye inspection CubeSat

The space community is moving forward with the development of in-orbit servicing and removal technologies to enable the circular economy in space and improve future space missions’ scientific and commercial return and space environment exploitation. The application of nanosatellites to carry out proximity operations presents an additional opportunity to support various novel and cost-effective distributed mission architectures. The SpEye CubeSat mission, funded by the Agenzia Spaziale Italiana in the framework of the Alcor Program, aims at demonstrating inspection and rendezvous guidance navigation and control capabilities of a nanosatellite in close-proximity of the satellite carrier in a low Earth orbit environment. This paper focuses on the design of the SpEye mission and on the guidance and control strategies to enable its technological demonstrations. Particular attention is placed on the safety aspects of trajectory design, considered of paramount importance for the robust autonomous operations of a low-cost CubeSat in proximity to another satellite.

Manipulating Hetero-Nanowire Films for Flexible and Multifunctional Thermoelectric Devices.

Flexible thermoelectric devices hold significant promise in wearable electronics owing to their capacity for green energy generation, temperature sensing, and comfortable wear. However, the simultaneous achievement of excellent multifunctional sensing and power generation poses a challenge in these devices. Here, ordered tellurium-based hetero-nanowire films are designed for flexible and multifunctional thermoelectric devices by optimizing the Seebeck coefficient and power factor. The obtained devices can efficiently detect both object and environment temperature, thermal conductivity, heat proximity, and airflow. In addition, combining the thermoelectric units with radiative cooling materials exhibits remarkable thermal management capabilities, preventing device overheating and avoiding degradation in power generation. Impressively, this multifunctional electronics exhibits excellent resistance in extreme low earth orbit environments. The fabrication of such thermoelectric devices provides innovative insights into multimodal sensing and energy harvesting.

The Spectral Characterization of Novel Spacecraft Materials in the Low Earth Orbit Environment

The Spectral Characterization of Novel Spacecraft Materials in the Low Earth Orbit Environment

The Thermo-Mechanical Properties of Carbon-Fiber-Reinforced Polymer Composites Exposed to a Low Earth Orbit Environment

In this study, we focus on 3D-printed PEEK/CFRTP (Carbon-Fiber-Reinforced Thermoplastic) and PEEK (Polyether Ether Ketone) materials as new space materials. In space, there are intense ultraviolet (UV) rays that are weakened by the atmosphere on Earth, so it is essential to understand the degradation of materials due to UV rays in advance. Therefore, we developed a materials science experiment called the Material Mission, which will be carried out on board Ten-Koh 2. This mission measures the coefficient of thermal expansion (CTE) of the CFRTP samples and the PEEK samples in LEO without recovery. So, we developed a thermal expansion observation system to be installed on the Ten-Koh 2 satellite. In addition, UV irradiation tests simulating the UV environment in LEO were conducted as ground tests. From the results of the ground tests, it was possible to determine in advance the degree of degradation of each material in the UV environment, even up to 100 ESD. By utilizing these results in mission operations, more meaningful measurement results can be obtained, and this mission development can contribute greatly to developing new space materials in the future.

Fast Spacecraft Charging Mitigation With Plasma Contactors During High‐Power Electron Beam Emission in the GEO Environment

AbstractThe emission of artificial electron beams causes an active spacecraft charging effect that poses challenges for electron beam sounding experiments. Plasma contactors have been suggested as a potential solution to this issue based on theoretical and simulation studies, but the impact of these contactors on spacecraft potentials in complex space environments remains unexplored. This paper investigates the fast active charging effect of spacecraft under the action of plasma contactors in the geostationary Earth orbit environment by using a two‐dimensional Particle‐in‐Cell model. We analyze and compare the effects of the “ion emission” process of the plasma contactor and the “electron collection” process of the background plasma on the spacecraft potential at different beam and environment parameters, as well as the coupling effects when both processes occur simultaneously. Our findings indicate that the “ion emission” and “electron collection” processes are the primary factors in determining the spacecraft potential in relatively thin and dense plasma environments, respectively. When the two processes occur together, the contactor plasma cloud increases the “electron collection” return current by expanding the range of the positive potential area around the spacecraft, while the dense background plasma mediates and provides the return current to ensure that the plasma contactor can effectively suppress the active charging effect even after the ion sheath is present. These results suggest that a reasonable adjustment of the contactor parameters based on the relationship between the electron beam and the background environment can effectively extend the normal emission time of the electron beam.

High-efficiency radiation attenuation shields of polymer composites for the low earth orbit space environment – multilayer shielding simulation system-based investigations

The polymer/metal hybrids have been used as a solution for the mitigation of ionizing radiation in space for sensitive electronics components, particularly for a proton-rich Low Earth Orbit (LEO) environment. Consequently, radiation attenuation analysis of polymer/metal hybrid composites has been investigated. Radiation attenuation analysis has been performed using online GEANT4 (simulation toolkit) and the Multilayer Shielding Simulation System (MULASSIS) for the LEO space environment. The shielding potential of polymers, such as poly(dimethyl siloxane), poly(methyl methacrylate), polyurethane and ultra-high molecular weight polyethylene, were analyzed with optimized compositions. It was observed that the pristine PDMS attenuated relatively more radiations than other polymer matrices. For modelling of hybrid radiation material composition, PDMS and carbon fibre fabric-derived composite laminates along with metal sheets (Aluminum Al, Tantalum Ta or Tungsten W) were used to analyze hybrid compositions. Here, hybrid composition performance was analyzed as a function of various areal densities. Analyzed polymer laminate/metal hybrid compositions performed better to attenuate LEO radiations up to 42.29%, compared to conventional Al (areal densities of 0.2–1.0 g/cm2). The maximum magnitude of attenuation was found at an areal density of 1.0 g/cm2 for Ta and W metal composition (39.44% and 42.29%, respectively), and so performed better than Al metal. Improved attenuation ratios of the hybrid compositions revealed that the hybrid laminate/metal shields can replace conventional Al shields towards LEO space radiations.

Robustness analysis and station-keeping control of an interferometer formation flying mission in low Earth orbit

The impact of formation flying on interferometry is growing over the years for the potential performance it could offer. However, it is still an open field, and many studies are still required. This article presents the basic principles behind interferometry focusing first on a single array and secondly on a formation of satellites. A sensitivity analysis is carried out to evaluate how the performance of the interferometry is affected by an error in the relative position in the formation geometry. This is estimated by computing the loss of the performance in terms of percentage deviation due to a non-nominal relative trajectory, including two-dimensional errors and defining a payload index. The main goal of this study is to estimate whether some errors in the relative state are more impacting than others. The final objective is to compute the link between a position error and a specific loss of performance, to foresee the origin of the the error. Furthermore, a dynamical model is developed to describe the relative motion in the Low Earth Orbit environment, considering both the unperturbed and the J2 and drag contributions. A Proportional, Integral and Derivative controller is implemented for the position control of a multiple satellite formation flying, considering a low thrust control profile. The Formation Flying L-band Aperture Synthesis study is taken as the case scenario, analysing both nominal and non-nominal configurations. This study serves as a starting point for the development of a combined tool to assess the performance of the interferometry and the control on the relative state for future remote sensing studies involving relative motion.

Surface Degradation of Thin-Layer Al/MgF2 Mirrors under Exposure to Powerful VUV Radiation.

Thin-layer Al/MgF2 coatings are currently used for extraterrestrial far-UV astronomy as the primary and secondary mirrors of telescopes (such as "Spektr-UF"). Successful Hubble far-UV measurements have been performed thanks to MgF2 on Al mirror coatings. Damage of such thin-layer coatings has been previously studied under exposure to high-energy electrons/protons fluxes and in low Earth orbit environments. Meanwhile, there is an interest to test the stability of such mirrors under the impact of extreme radiation fluxes from pulsed plasma thrusters as a simulation of emergency onboard situations and other applications. In the present studies, the high current and compressed plasma jets were generated by a laboratory plasma thruster prototype and operated as effective emitters of high brightness (with an integral overall wavelength radiation flux of >1 MW/cm2) and broadband radiation. The spectrum rearrangement and hard-photon cut-off at energy above Ec were implemented by selection of a background gas in the discharge chamber. The discharges in air (Ec ≈ 6 eV), argon (Ec ≈ 15 eV) and neon (Ec ≈ 21 eV) were studied. X-ray diffraction and reflectometry, electron and atomic force microscopy, and IR and visible spectroscopy were used for coating characterization and estimation of degradation degree. In the case of the discharges in air with photon energies of E < 6 eV, only individual nanocracks were found and property changes were negligible. In the case of inert gases, the energy fraction was ≈50% in the VUV range. As found for inert background gases, an emission of such hard photons with energies higher than the MgF2 band gap energy of ≈10.8 eV caused a drastic light-induced ablation and degradation of the irradiated coatings. The upward trend of degradation with an increasing of the maximum photon energies was detected. The obtained data on the surface destruction are useful for the design of methods for coating stability tests and an understanding of the consequences of emergencies onboard space research stations.

Assessment of radiation shielding properties of self-healing polymers and nanocomposites for a space habitat case study under GCR and LEO radiation

In recent decades, the opportunity to introduce self-healing materials within space structures has drawn the attention of scientists and companies. Autonomous repair following damage caused by impacts with micrometeoroids and orbital debris (MMOD) would lead to safer human activity in space and would increase spacecraft operational life and autonomy, thus reducing replacement costs and possibly relieving astronauts from maintenance activities. In particular, integrating self-healing materials into structures to protect humans from the space environment is a fundamental step in the realization of long-lasting space exploration missions. Nevertheless, the way these materials interact with the environmental factors in space still needs to be properly analyzed and understood; in particular, space radiation is a serious threat to human health and material integrity. The proposed work hence investigates the shielding ability of candidate self-healing materials with the specific purpose of human protection in crewed missions. The NASA HZETRN2015 (High Z and Energy TRaNsport, 2015 version) software is used to simulate galactic cosmic rays (GCR) and low Earth orbit (LEO) environment. A comparison between a standard habitat layup proposed by NASA and a set of configurations containing self-healing polymers is performed to verify that the substitution of conventional bladder materials with the proposed self-healing solutions does not decrease the overall habitat shielding performance. A self-healing nanocomposite option with single-walled carbon nanotubes (SWCNTs) is also analyzed to determine whether the insertion of nanofillers can increase the overall shielding performance. In the second phase, the comparison of puncture tests on blank and irradiated samples under conditions reproducing a space suit example is presented to assess the possible effects of radiation on the self-healing performance.

Electrostatic Potential Shielding in Representative Cislunar Regions

Touchless potential sensing of neighboring spacecraft using photoemissions and secondary electron emissions has been investigated for geosynchronous (GEO) applications. As more missions are being sent to cislunar space, this technology may be extended there as well. However, the complexity of the cislunar environment presents novel challenges for touchless potential sensing technology. A chief issue is shorter Debye lengths than in GEO regions, which can be as low as 10 m in the cislunar regions. Therefore, a model for the electric and potential fields surrounding a charged spacecraft in short Debye regions around the moon is investigated. The vacuum (Laplace) and Debye–Hückel models are presented and effective Debye lengths are used to expand the models and better represent the environment. The effective Debye length has previously been investigated in low Earth orbit (LEO), quiet GEO, and asteroid environments but has not been found in the cislunar plasma environment, and a larger effective Debye length may allow touchless potential sensing using electron emissions to be possible at farther, safer distances than expected. Once the effective Debye lengths and associated models are established, the relationship between effective Debye lengths and touchless potential sensing capabilities is explored through computations in NASCAP-2k, a spacecraft–plasma interaction software. The developed methods are then used to determine whether passive and active touchless potential sensing is feasible in cislunar regions with nonnegligible electrostatic potential shielding.

Protecting satellites in low Earth orbit: An overview of hazards and policy solutions

Satellites in the Low Earth Orbit (LEO) environment face various hazards which threaten the long-term sustainability of the space economy. This article describes the potential dangers to satellites in LEO beyond commonly referenced orbital debris and satellite collisions, including hazards that arise from the LEO environment itself and from other anthropogenic sources such as laser interference and orbital light pollution. As the LEO economy surges in the coming decade, preventative policy such as that proposed in this article could address these risks before they become an issue and ensure that the LEO environment continues to grow sustainably.

Carbon Nanotube Based Broadband Solar Thermal Absorber Coatings

Radiant energy conversion and storage eliminate the mass transfer process induced power output limitation, and open a new vista for energy utilization. An effective system for harvesting radiant energy from both solar and thermal radiation will be beneficial for further radiant energy utilization. On the other hand, space observatory missions require low-reflectivity surfaces/coatings for space-borne instruments, such as seeker telescopes, optical sensors, etc., to minimize stray and reflected light on targeted telescope and baffle materials and construction. The excellent optical, thermal, and mechanical properties of carbon nanotubes (CNTs) make them as ideal coating materials for absorbing the broadband spectrum across UV-Vis-IR regions.In this presentation, Faraday Technology will discuss an innovative electrophoretic deposition (EPD) manufacturing process, based on the use of pulsed electric fields, for controlled, reproducible, scalable deposition of a wide variety of carbon nanotube based coatings across a broad range of substrates, geometries and sizes (Figure 1 a). The effects of waveforms, electrolytes, substrates, etc. on the formation of robust and uniform coating will be discussed in this talk. The optical properties, and environmental survivability of carbon nanotube coatings will be demonstrated via a variety of testing or characterizations. The CNT coatings show the total hemispherical reflection of 0.5% - 1% across UV-Vis to near infrared (NIR) wavebands, which is much lower than the reflectance of the typically used Z306 black paint (Figure 1 b). These CNT coatings also withstood simulated launch conditions vibrational tests, and demonstrated no weight loss and optical degradation. Furthermore, the CNT coatings were evaluated for atomic oxygen erosion resistance in a simulated low earth orbit (LEO) environment, and showed enhanced resilience when compared to Kapton and HOPG. Faraday will also introduce their applications in low-reflective coatings and solar thermal absorbers for radiant energy harvesting and conversion.In summary, a scalable EPD manufacturing process for fabricating carbon nanotube based coatings have been developed at Faraday for the applications in the field of low-reflective coatings and broadband solar thermal absorbers.Acknowledgements: The financial support from NASA SBIR program through contracts No. 80NNSC18P2062 & 80NSSC19C0177, DARPA SBIR program through grant No. W31P4Q-22-C-0014, DOD MDA STTR program through grant No. HQ0147-19-C-7065, and DOD Air Force SBIR program through grant No. FA9550-22-P-0015 are acknowledged. Figure 1

Direct Printing Composite Materials by Electro-Codeposition

We are developing an on-demand direct metal printing technology that can utilize the unique advantages of manufacturing in a zero-gravity Low Earth Orbit (LEO) environment, to produce value-added next generation materials that are challenging to manufacture terrestrially. One such class of materials, covetics (nanocarbon-infused metals), are inherently difficult to produce on Earth but have great in-space and terrestrial commercial potential due to their enhanced physicochemical properties, such as higher thermal/electrical conductivity and higher strength at lower mass as compared to conventional wrought metals.Specifically, this talk will highlight an ongoing activity at Faraday to directly print composite nanowires via a pulse electro-codeposition approach. This activity has indicated that these composite materials can achieve a greater than 50% reduction in sheet resistance and a ~50% increase in mechanical strain compared to Cu foils. We will also discuss the opportunity to produce a wide range of material shapes by enabling a direct print apparatus that combines x,y,z control methods with an electro-codeposition printhead. If successful, we envision that the method to print next generation composite materials like ‘covetics’ has the potential to meet many of the electronics and space community’s needs by enabling in-space structural repairs, fabrication of new electronic components or sensors, or be utilized as heat exchanger composite materials.Acknowledgements: Faraday Technology acknowledges the NASA SBIR activities under 80NSSC22CA99.

Resistance of amorphous TiAlCrZrSi/polyimide high entropy alloy films to atomic oxygen erosion

To alleviate the atomic oxygen (AO) degradation of the polyimide deployed in the low Earth orbit (LEO) environment, we fabricate a set of amorphous TiAlCrZrSi/polyimide films under various negative bias values via the 3rd generation co-filter cathode vacuum arc (C-FCVA). Our rational technical design realizes the noninterference regulation and filtration of mixed multielement plasma compositions. In addition, the atomic size difference (δ, 0.075–0.081), mixing enthalpy (ΔHmix, −48.98 to −46.84 kJ mol−1), and mixing entropy (ΔSmix, 12.83–12.91 J K−1 mol−1) are all within the range of parameters required for the formation of amorphous TiAlCrZrSi high-entropy alloys (HEAs). Moreover, the TiAlCrZrSi/polyimide (no bias) film can realize an equilibrium of AO resistance and durability (Ey = 2.02 × 10−26 cm3 atom−1), which is only 0.67 % of that calculated for pristine polyimide. This can be attributed to the excellent AO penetration barrier ability of the generated HEA oxide scales. Furthermore, the thickening of HEA films can reduce the sensitivity of residual defects to AO undercutting erosion, as discussed by the existing empirical theoretical models.

Atomic oxygen degradation of a fluorine-containing colorless polyimide

Colorless polyimides (PIs) are regarded as the most feasible lens materials deployed in aerospace optical systems due to their light weight, flexibility, transparency, and excellent mechanical properties. However, durability towards atomic oxygen (AO) exposure is a chief concern for externally deployed colorless PI films in low Earth orbit (LEO) environments. In this work, we investigated the degradation behavior of a fluorine-containing colorless PI film with a combination of ground-based AO exposure experiments and reactive molecular dynamics (ReaxFF-MD) simulations. The fluorine-containing colorless PI showed linear erosion dynamics and a constant erosion yield (Ey) of ∼1.4 × 10−24 cm3 atom−1. Microscopic investigations demonstrated an increased surface roughness and shag-like appearance after continuous AO exposure. In addition, spectroscopic transformations resulted from elimination and oxidation processes occurring at specific reaction active sites (C=O, CN, CH, and CF, and CC) and the release of volatile substances. Moreover, the exposed fluorine-containing colorless PI films exhibited gradually deteriorating visible light transmission with increased AO fluence. Furthermore, the ReaxFF-MD simulations demonstrated physical sputtering and bombardment-enhanced chemical reaction models. Considering the limited-scale slab and the system thermal dissipation, the experimental and ReaxFF-MD computational results were largely consistent.

Advances in atomic oxygen resistant polyimide composite films

Polyimide (PI) film is an attractive space material used in low Earth orbit (LEO) environment, owing to its extraordinary thermal, chemical stability, flexibility, excellent mechanical and insulating properties. These superior properties and versatility make PI one of the indispensable materials ensure the normal operation of spacecraft, which are unparalleled by most other polymers. Hydrocarbon-based PI, however, cannot withstand the erosion of atomic oxygen (AO) in LEO. Up to now, many strategies including coating, matrix modification and structural design have been utilized to improve the AO resistance of PI film. This review summarizes the state-of-the-art works on the PI composite films with AO resistance, and discusses the advantages and disadvantages of different strategies for protecting PI matrix from AO erosion. First, we discuss the conventional coatings protection, which contains inorganic, organic and organic–inorganic coatings. Then, the focus is attached to improving the inherent anti-AO capacity of PI film through matrix modifications, such as intrinsic, blending and doping modification strategies. Finally, the structural design strategies including Janus structure and bioinspired microstructure are also discussed. Fundamental parameters of PI composite films, such as mass loss, erosion yield, as well as mechanical properties, are highlighted to evaluate their anti-AO ability. Inspired by investigations over the past decades, a roadmap is also carefully depicted for the future of AO-resistant PI composite films in fundamental research.

Feasibility Study of the Bare-Photovoltaic-Tether Concept: Prototypes and Experimental Performance Evaluation of the Photovoltaic Tether Segment

Consumable-free electron emitters are presently not feasible for autonomous tether-based deorbit devices such as E.T.PACK due to their power requirement. The bare-photovoltaic-tether (BPT) concept combines the bare tether electron collection with a tether segment, coated with thin film Copper Indium Gallium Selenide solar cells to harvest additional power for the cathodic contact, potentially enabling propellant-less operation. This thesis presents the first prototype of the photovoltaic tether segment, its architecture, its electrical characteristics, major challenges of the system and possible solutions. Photovoltaic tether segments of up to 3 m in length were manufactured, consisting of parallelized submodules of 25 cm in length. Due to space limitations, only the I-V-characteristics of these submodules were measured under a self-built Class BCA LED Solar-Simulator inside a vacuum chamber and at varying temperatures between −100 °C and 100 °C. In addition, the suitability of the concept for a low Earth orbit environment was assessed by performing atomic oxygen exposure tests using a microwave-based low pressure plasma atomic oxygen source. Based on the experimental data, a model is provided for predicting the performance of the photovoltaic segment in orbit, highlighting the main problems of the BPT: temperature, orientation and partial shading.

Trending and analysis of payload vs. All low earth conjunction data messages below 1000 km, from 2016 through 2021

The Air Force Safety Center is developing a program to quantify the distribution of risks to the orbital environment across time and space by trending and analyzing orbital conjunction events. Previous efforts described automating the intake of Conjunction Data Messages (CDM) previously generated by the 18th and 19th Space Defense Squadrons (18 SDS, 19 SDS) and developing pre-processing scripts necessary to populate information germane to orbital collision risk assessment. The intent of the current effort is to account not only for the probability of collision (Pc), but also the consequence of the debris products from a collision to the low Earth orbital environment, should it occur. To accomplish this, the team analyzed all reported CDMs of conjunction events below 1000 km in altitude, between 1 Jan 2016 and 31 Dec 2021. 18 SDS reported Pcs were re-computed using the Foster-92 method. A circular 2-dimensional interaction area was applied instead of a square, to reduce conservatism and lend closer towards realism. Hard Body Radii estimates were pooled from externally sourced information, including The Aerospace Corporation and various open sources. When not available, radius estimates were imputed based on available data. Covariance information was sourced from CDMs. For consequence, the amount of damaging, lethal non-trackable and trackable debris products were estimated using The Aerospace Corporation's IMPACT 8.0 model. The model accounts for relative velocity, object masses, mass distribution, and structure. Object distribution and structure were inferred from the object type field in the CDMs. Relative velocity was also sourced from CDMs. The object masses were sourced from data furnished by The Aerospace Corporation and Union of Concerned Scientists satellite database. The expected number of damaging, lethal non-trackable, and trackable debris products were multiplied by the Pc to produce a quantitative risk metric for each conjunction event. Risks were adjusted to account for likely collision avoidance maneuvers based on satellite age, mass, and Pc. The results show a logarithmic increase in total risk over time, particularly after 2020. This change correlates to the launch of Starlink and OneWeb satellites into orbit, and analysis confirmed that the uptick in risk is attributable to the launch of those large constellations into orbit. The risk metric for Starlink vs. Starlink conjunctions was further adjusted to more accurately account for proprietary processes and high accuracy ephemerides which enables better information for performing collision avoidance maneuvers. This adjustment reduced the slope of the risk trends starting in 2020, but they are still positive and logarithmic. Spatial domain analysis revealed that the preponderance of debris production risk for reported conjunctions below 1,000 km resides between the altitudes of 450 km and 850 km. The spatial distribution of risk by altitude changed starting in 2020 due to the launch of large constellations, resulting in a higher and more evenly distributed risk of debris production between 350 and 1,000 km. Results also indicate that more trackable debris would have likely been generated by collisions between payloads and trackable objects, with perigees below 1,000 km than the 37 that have been confirmed and cataloged during that time period. However, analysis of the four confirmed payload collision events with cataloged debris produced a bootstrapped confidence interval of trackable debris generated per year suggesting the trackable debris production rate estimated here is within a plausible range. Planned future work looks to address known assumptions and limitations. This work is the first known effort to quantitatively analyze historical risks of conjunction events using full sets of CDM data and fuse them with the latest semi-analytical breakup algorithms. Analyses such as these are necessary to better inform ongoing and future Space Safety and Space Traffic Management policy development efforts within the US Government and internationally.