This work investigates a novel signature for measuring the Ni/Fe ratio on the asteroid (16) Psyche that is robust against interference from large Solar Particle Events. NASA's Psyche mission launched ...on October 13th, 2023, and is headed to investigate this M-type asteroid. A primary science requirement for the Psyche gamma-ray spectrometer is to measure the absolute surface abundance of Ni and Fe. In particular, the Ni/Fe ratio will help test the hypothesis that (16) Psyche is a metal-rich body, possibly a remnant core from a failed planetesimal. However, Solar Particle Events can activate iron in the spacecraft, as well as the body of Psyche itself, disrupting the measurement of the surface abundance of iron for six months or more. Such an event happened during NASA's MESSENGER mission in orbit around Mercury on June 4, 2011, precluding further mapping of iron for the remainder of the mission. A similar event at Psyche could adversely affect mission science goals and/or prolong operation. Given the expected high abundance of Fe at Psyche, this paper proposes an alternative signature that relies on gamma rays from 54Fe rather than 56Fe. Although 54Fe has a lower natural abundance than 56Fe (5.8% vs 91.7%, respectively), 54Fe is much less susceptible to interference from activation and would allow measurements of the surface abundance of iron to resume within days after a large Solar Particle Event. In addition, 58Ni is shown not to be susceptible to interference from activation, thus making the 58Ni/54Fe ratio a robust alternative signature in the presence of Solar Particle Events.
Some years ago, the consensus was that asteroid (16) Psyche was almost entirely metal. New data on density, radar properties, and spectral signatures indicate that the asteroid is something perhaps ...even more enigmatic: a mixed metal and silicate world. Here we combine observations of Psyche with data from meteorites and models for planetesimal formation to produce the best current hypotheses for Psyche's properties and provenance. Psyche's bulk density appears to be between 3,400 and 4,100 kg m−3. Psyche is thus predicted to have between ~30 and ~60 vol% metal, with the remainder likely low‐iron silicate rock and not more than ~20% porosity. Though their density is similar, mesosiderites are an unlikely analog to bulk Psyche because mesosiderites have far more iron‐rich silicates than Psyche appears to have. CB chondrites match both Psyche's density and spectral properties, as can some pallasites, although typical pallasitic olivine contains too much iron to be consistent with the reflectance spectra. Final answers, as well as resolution of contradictions in the data set of Psyche physical properties, for example, the thermal inertia measurements, may not be resolved until the NASA Psyche mission arrives in orbit at the asteroid. Despite the range of compositions and formation processes for Psyche allowed by the current data, the science payload of the Psyche mission (magnetometers, multispectral imagers, neutron spectrometer, and a gamma‐ray spectrometer) will produce data sets that distinguish among the models.
Plain Language Summary
Since the NASA mission to asteroid (16) Psyche was selected, interest from the public and from the scientific community in the asteroid has risen considerably. New observations of the asteroid's physical properties indicate a different composition than earlier data had shown. A decade ago, much of the community thought the asteroid was 90% metal on its surface. There are still contradictions in the compilation of all current data, but the best analysis indicates that Psyche's density is between 3,400 and 4,100 kg m−3, indicating it is a mixture of rock with between 30 and 60 vol% metal.
Key Points
New observations of asteroid (16) Psyche's physical properties indicate a different composition and properties than earlier data had shown
The best current analysis indicates that Psyche's density is 3,400‐4,100 kg m‐3, indicating a mixture of rock with 30‐60 vol% metal
Contradictions in data of Psyche physical properties may not be resolved until the NASA Psyche mission arrives at the asteroid
Context. Asteroid (16) Psyche is the target of the NASA Psyche mission. It is considered one of the few main-belt bodies that could be an exposed proto-planetary metallic core and that would thus be ...related to iron meteorites. Such an association is however challenged by both its near- and mid-infrared spectral properties and the reported estimates of its density. Aims. Here, we aim to refine the density of (16) Psyche to set further constraints on its bulk composition and determine its potential meteoritic analog. Methods. We observed (16) Psyche with ESO VLT/SPHERE/ZIMPOL as part of our large program (ID 199.C-0074). We used the high angular resolution of these observations to refine Psyche’s three-dimensional (3D) shape model and subsequently its density when combined with the most recent mass estimates. In addition, we searched for potential companions around the asteroid. Results. We derived a bulk density of 3.99 ± 0.26 g cm−3 for Psyche. While such density is incompatible at the 3-sigma level with any iron meteorites (∼7.8 g cm−3), it appears fully consistent with that of stony-iron meteorites such as mesosiderites (density ∼4.25 g cm−3). In addition, we found no satellite in our images and set an upper limit on the diameter of any non-detected satellite of 1460 ± 200 m at 150 km from Psyche (0.2% × RHill, the Hill radius) and 800 ± 200 m at 2000 km (3% × RHill). Conclusions. Considering that the visible and near-infrared spectral properties of mesosiderites are similar to those of Psyche, there is merit to a long-published initial hypothesis that Psyche could be a plausible candidate parent body for mesosiderites.
Fischer-Tropsch (F-T) process is an important synthesis route to acquire clean liquid fuels through modern coal chemical industry, which converts syngas (CO and H2) into hydrocarbon, and also ...generates oxygenates discharged as the F-T waste-water. These oxygen-containing compounds in F-T waste-water have the similar molecular weight and some are even isomers of each other. Hence, it is necessary to develop rapid and efficient analysis tools to obtain identification and quantitative information of the F-T waste-water. The pure shift NMR techniques provided only chemical shift information in one-dimension 1H NMR spectra, without homonuclear JH-H coupling. In this work, we tested and compared three pure shift NMR techniques (including Zangger-Sterk, PSYCHE and TSE-PSYCHE methods) in the analysis of two F-T waste-water model mixtures, genuine waste-water and two alcohol isomer mixtures. The results show that JH-H coupling multiplicities are collapsed into singlets corresponding to individual chemically distinct protons of the compound. For some severely overlapped signals in the pure shift NMR spectra, the chemical shift selective filters with TOCSY (CSSF-TOCSY) experiments were conducted to assist the signal assignment. Thus, pure shift NMR approaches can identify most signals of components, and CSSF-TOCSY can extract the signal of a specific compound. The combination of these two NMR techniques offers a powerful tool to analyze the F-T waste-water or other complex mixtures including isomer mixtures.
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•1D pure shift NMR methods were first time applied to analyze the Fischer-Tropsch wastewater mixtures, which simplifies the spectroscopy assignment by suppressing the homonuclear coupling. Three pure shift NMR methods (Zangger-Sterk, PSYCHE and TSE-PSYCHE) were tested and compared.•CSSF-TOCSY was applied to extract the unambiguous individual 1H NMR spectrum effectively.•The combination of the pure shift NMR and CSSF-TOCSY provides a versatile, rapid and efficient tool for the analysis of the complex mixtures, such as the F-T wastewater and isomer mixtures.
This work investigates a novel signature for measuring the Ni/Fe ratio on the asteroid (16) Psyche that is robust against interference from large Solar Particle Events. NASA's Psyche mission launched ...on October 13th, 2023, and is headed to investigate this M-type asteroid. A primary science requirement for the Psyche gamma-ray spectrometer is to measure the absolute surface abundance of Ni and Fe. In particular, the Ni/Fe ratio will help test the hypothesis that (16) Psyche is a metal-rich body, possibly a remnant core from a failed planetesimal. However, Solar Particle Events can activate iron in the spacecraft, as well as the body of Psyche itself, disrupting the measurement of the surface abundance of iron for six months or more. Such an event happened during NASA's MESSENGER mission in orbit around Mercury on June 4, 2011, precluding further mapping of iron for the remainder of the mission. A similar event at Psyche could adversely affect mission science goals and/or prolong operation. Given the expected high abundance of Fe at Psyche, this paper proposes an alternative signature that relies on gamma rays from 54Fe rather than 56Fe. Although 54Fe has a lower natural abundance than 56Fe (5.8% vs 91.7%, respectively), 54Fe is much less susceptible to interference from activation and would allow measurements of the surface abundance of iron to resume within days after a large Solar Particle Event. In addition, 58Ni is shown not to be susceptible to interference from activation, thus making the 58Ni/54Fe ratio a robust alternative signature in the presence of Solar Particle Events.
•The asteroid (16) Psyche is hypothesized to be the remnant core of a planetesimal.•Large Solar Events can interfere with the detection of iron on the surface.•Iron and nickel signatures, which are robust to Solar Events, have been identified.•The 1408 keV gamma ray from 54Fe is robust against activation from Solar Events.
Introduction. This paper considers madness as a metahistorical category of culture as well as an excluded language in Western European culture that exists despite the language code. To determine the ...status of madness in the contemporary philosophy the author analyses the way it functions in the discourse of “the other”. Theoretical analysis. The exclusion of madness from the context of philosophical research occurred due to such various markers changing from era to era as a lie, delusion, nonsense, buffoonery, and finally the dysfunction of the mind completed by Pinel’s reform. The definition of madness as a forbidden language comes from two theses: 1) mental disorders result from biological, not socio-psychological problems; 2) madness and a mental disorder are not two different configurations, they have organic nature that is to be neutralized in terms of pharmacology and defined in terms of behavioral deviations, and that excludes subjective and nonphysical suffering. Conclusion. The research relevance is obvious because modern aesthetics and philosophy with the cultural model of insanity as a core concept need further elaborating. The duality of the subject of psychiatry concerning the human personality implies that this component must be taken into account apart from exclusively natural-scientific studies.
The asteroid (16) Psyche may be the metal-rich remnant of a differentiated planetesimal, or it may be a highly reduced, metal-rich asteroidal material that never differentiated. The NASA Psyche ...mission aims to determine Psyche’s provenance. Here we describe the possible solar system regions of origin for Psyche, prior to its likely implantation into the asteroid belt, the physical and chemical processes that can enrich metal in an asteroid, and possible meteoritic analogs. The spacecraft payload is designed to be able to discriminate among possible formation theories. The project will determine Psyche’s origin and formation by measuring any strong remanent magnetic fields, which would imply it was the core of a differentiated body; the scale of metal to silicate mixing will be determined by both the neutron spectrometers and the filtered images; the degree of disruption between metal and rock may be determined by the correlation of gravity with composition; some mineralogy (e.g., modeled silicate/metal ratio, and inferred existence of low-calcium pyroxene or olivine, for example) will be detected using filtered images; and the nickel content of Psyche’s metal phase will be measured using the GRNS.
Beginning from embryological development, skin and psyche are closely related to physiological state regardless of age. Altering the homeostasis of one of these components impacts on the other, ...thereby substantiating that the relationship between itch and psyche is bilateral. Itch has a complex pathogenesis, which involves the peripheral and central nervous systems, as well as various inflammatory mediators. This paper reviews key aspects of itch pathogenesis, relevant associations with stress, the contagiousness of itch, psychological and psychiatric considerations related to itch, and the burden of itch with respect to impairment of health-related quality of life (HRQoL) and stigmatization. Despite the fact that itch-psyche associations still pose many questions, current knowledge supports the role of a holistic, interdisciplinary approach to these patients in order to improve their well-being.
The National Aeronautics and Space Administration (NASA) Psyche mission will visit the 226‐km diameter main belt asteroid (16) Psyche, our first opportunity to visit a metal‐rich object at close ...range. The unique and poorly understood nature of Psyche offers a challenge to the mission as we have little understanding of the surface morphology and composition. It is commonly accepted that the main evolutionary process for asteroid surfaces is impact cratering. While a considerable body of literature is available on collisions on rocky/icy objects, less work is available for metallic targets with compositions relevant to Psyche. Here we present a suite of impact experiments performed at the NASA Ames Vertical Gun Range facility on several types of iron meteorites and foundry‐cast ingots that have similar Fe‐Ni compositions as the iron meteorites. Our experiments were designed to better understand crater formation (e.g., size, depth), over a range of impact conditions, including target temperature and composition. We find that the target strength, as inferred from crater sizes, ranges from 700 to 1,300 MPa. Target temperature has measurable effects on strength, with cooled targets typically 10–20% stronger. Crater morphologies are characterized by sharp, raised rims and deep cavities. Further, we derive broad implications for Psyche's collisional evolution, in light of available low resolution shape models. We find that the number of large craters (>50 km) is particularly diagnostic for the overall bulk strength of Psyche. If confirmed, the number of putative large craters may indicate that Psyche's bulk strength is significantly reduced compared to that of intact iron meteorites.
Plain Language Summary
Many iron meteorites are thought to be remnants of the cores of melted asteroids. Some cores may have been exposed by collisions during the earliest days of Solar System history, with a few survivors possibly found today in the main asteroid belt. National Aeronautics and Space Administration (NASA) Psyche mission will be the first spacecraft to visit asteroid (16) Psyche, an object thought to be representative of these metallic asteroids. Impacts onto (16) Psyche in the past may therefore be able to tell us about the history and nature of this body. To this end, we performed high‐speed impact experiments into metallic targets in order to understand how crater formation differs from rocky bodies. These experiments revealed that impact craters into metal targets are deeper and have sharper rims than on their rocky counterparts. These results will be crucial for interpreting both the bulk properties of Psyche's interior and the modification of Psyche's surface when the Psyche mission reaches its target.
Key Points
We quantify morphological properties of cratering in metallic targets.
We derive implications for the Psyche mission.
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