Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “asteroids”

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

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

At least 1,297 records · Page 72

Analysis of Samples from Asteroid Ryugu Returned by Hayabusa2

After returning to Earth in the winter of 2020, the samples from Cb-type asteroid Ryugu were stored under atmosphere-free conditions at the Extraterrestrial Materials Curation Center of ISAS/JAXA, and investigated for basic descriptions (sample imaging, weighing, etc.). They were distributed to six initial analysis teams in Japan in June 2021. The "Stone" team, in charge of analysis of coarse particles (>1 mm in size), conducted a series of analyses using a variety of techniques including reflectance spectra measurement, synchrotron-radiation three-dimensional elemental and mineralogical analysis, bulk elemental analysis using muon beam, Fe valence state measurement by XANES and Mössbauer spectroscopy, detailed mineralogical and petrological characterization by scanning and transmission electron microscopes. Physical and thermal properties of Ryiugu samples were measured to understand the response to shock and heating. In this talk, I would like to introduce summary of analysis results and what comes to be known about the formation and evolution of asteroid Ryugu.

Tomoki Nakamura↗

Space weathering features of anhydrous minerals in fine grains from the C-type asteroid Ryugu

Materials exposed to the space environment are expected to show optically and chemically modified properties. This process is called as space weathering and is caused mainly by micrometeoroid bombardments and solar wind implantation [1]. Thus far, the space weathering of carbonaceous asteroids has not been well understood. Regolith samples were successfully recovered from C-type asteroid Ryugu by the Hayabusa mission [2]. Ryugu samples will provide insights into the ongoing space weathering of Ryugu [3]. In this study, we investigated the space weathering of anhydrous minerals including iron sulfides, magnetite, and carbonates, which are major reservoirs of volatiles including carbon, oxygen, and sulfur in Ryugu materials. We performed scanning electron microscopy (SEM) and transmission/scanning transmission electron microscopy (TEM/STEM) analysis for Ryugu samples.

Toru Matsumoto↗

Olivine Mineralogy of Asteroid Ryugu Samples and CI Chondrites: Further Evidence for their Common Origin

Initial analysis of asteroid Ryugu samples has revealed that they were mm-mm scale brecciamostly composed of aqueously altered phases (e.g., Mg-Fe phyllosilicates, carbonates) and showed remarkablesimilarities to CI chondrites in mineralogy and chemistry [e.g., 1,2]. Our detailed analysis of Ryugu samples hasdetected small amounts (<<1 vol.%) of unaltered silicates that would escape severe aqueous alteration [3]. Olivine isthe most abundant (>90 vol%) phase among such unaltered silicates. Although most Ryugu olivine grains aresmaller than 5 mm, they bear important information about the precursors of the parent Ryugu asteroid. In thisabstract we report additional results of olivine mineralogical study of Ryugu samples, and especially compare witholivine grains in CI chondrites (Ivuna and Orgueil) to further discuss their relationship and possible common origin.

T. Mikouchi↗

Shock-Induced Deformation Recorded in the Regolith Particles from C-Type Asteroid Ryugu

The Hayabusa 2 mission successfully returned with samples of C-type near-Earth asteroid (162173) Ryugu on December of 2020. Ryugu samples contain large quantities of volatiles such as water and noble gases. Studying Ryugu samples is a great opportunity to understand the shock metamorphism on water-bearing rubble-pile asteroids. In this study, we have examined shock metamorphism on sixteen coarse mm-sized particles recovered by the Hayabusa 2 mission.

M. Kikuiri↗

Presolar C- and O-rich Grains in the Matrix and a Clast in Asteroid Ryugu

Presolar grains formed in the outflows of dying stars and some have been preserved in primitive meteorites, interplanetary dust particles, and comet Wild 2 samples. Presolar silicates are one of the most abundant presolar phases, but are prone to destruction by parent body hydrothermal alteration. Refractory presolar phases, such as oxides and carbides, are more resistant to such alteration. Samples from asteroid Ryugu returned by JAXA’s Haya-busa2 mission show evidence for extensive aqueous alteration. To constrain the abundance of presolar grains in Ryugu, we conducted NanoSIMS isotopic mapping of fragments of a C0002 grain from Chamber C, perhaps from the asteroid sub-surface.

A N Nguyen↗

Double Asteroid Redirection Test (DART) Phase D Mission Design & Navigation Analysis

NASA’s Double Asteroid Redirection Test (DART) mission is the first demonstration of kinetic deflection of an asteroid. DART uses terminal guidance to impact Dimorphos, which orbits Didymos, during its 2022 close-approach to Earth. The close range to Earth allows Earth-based observations to reconstruct the impact’s effect. Light-curve data will be used to measure the resulting change in orbit period of Dimorphos due to the momentum change associated with the impact experiment. This paper describes the current DART trajectory and recent Mission Design and Navigation analysis preparing for launch.

Velez, Dianna↗

Characterizing Space Weathering Features in Grains From Asteroid Ryugu

Airless bodies such as asteroids are characterized by a lack of a protective atmosphere to guard against the effects of micrometeorite bombardment and solar wind irradiation. These processes, cumulatively known as space weathering, alter the microstructural and chemical properties of grains on asteroidal surfaces, signatures of which are recognized as vesiculated textures, amorphous grain rims, and fe-bearing nanoparticles. The accumulation of these features also causes changes in the optical properties of the surface regolith, complicating the interpretation of remote sensing data and the characterization of returned samples.

L. E. Melendez↗

Soluble Organic Molecules in Samples of the Carbonaceous Asteroid (162173) Ryugu

The Hayabusa2 spacecraft collected samples from the surface of the carbonaceous near-Earth asteroid (162173) Ryugu, and brought them to Earth. The samples were expected to contain organic molecules, which record processes that occurred in the early Solar System. We analyzed organic molecules extracted from the Ryugu surface samples. We identify a variety of molecules containing the atoms CHNOS, formed by methylation, hydration, hydroxylation, and sulfurization reactions. Amino acids, aliphatic amines, carboxylic acids, polycyclic aromatic hydrocarbons, and nitrogen-heterocyclic compounds were detected, with properties consistent with an abiotic origin. These compounds likely arose from aqueous reaction on Ryugu’s parent body and are similar to organics in Ivuna-type meteorites. These molecules can survive on the surfaces of asteroids and be transported throughout the Solar System.

Hiroshi Naraoka↗

PAHs, Hydrocarbons, and Dimethylsulfides in Asteroid Ryugu Samples A0106 and C0107 and the Orgueil (CI1) Meteorite

Evaluating the molecular distribution of organic compounds in pristine extraterrestrial materials is cornerstone to understanding the abiotic synthesis of organics and allows us to better understand the molecular diversity available during the formation of our solar system and before the origins of life on Earth. In this work we identify multiple organic compounds in solvent extracts of asteroid Ryugu samples A0106 and C0107 and the Orgueil meteorite using two-dimensional gas chromatography and time-of-flight high resolution mass spectrometry (GC×GC-HRMS). Our analyses found similarities between the molecular distribution of organic compounds in Ryugu and the CI carbonaceous chondrite Orgueil. Specifically, several PAHs and organosulfides were found in Ryugu and Orgueil suggesting an interstellar and parent body origin for these compounds. We also evaluated the common relationship between Ryugu, Orgueil, and comets like Wild-2; however, until comprehensive compound-specific isotopic analyses for these organic species are undertaken, and until the effects of parent body processes and Earth’s weathering processes on meteoritic organics are better understood, their parent-daughter relationships will remain unanswered. Finally, the study of organic compounds in Ryugu samples and the curation practices for the future preservation of these unvaluable materials are also of special interest for future sample return missions, including NASA’s OSIRIS-REx asteroid sample return mission.

Hayabusa2↗

The Spatial Distribution of Soluble Organic Matter and Their Relationship to Minerals in the Asteroid (162173) Ryugu

We performed in-situ analysis on a ~1 mm-sized grain A0080 returned by the Hayabusa2 spacecraft from near-Earth asteroid (162173) Ryugu to investigate the relationship of soluble organic matter (SOM) to minerals. Desorption electrospray ionization-high resolution mass spectrometry (DESI-HRMS) imaging mapped more than 200 CHN, CHO, CHO–Na (sodium adducted), and CHNO soluble organic compounds. A heterogeneous spatial distribution was observed for different compound classes of SOM as well as among alkylated homologues on the sample surface. The A0080 sample showed mineralogy more like an Ivuna-type (CI) carbonaceous chondrite than other meteorites. It contained two different lithologies, which are either rich (lithology 1) or poor (lithology 2) in magnetite, pyrrhotite, and dolomite. CHN compounds were more concentrated in lithology 1 than in lithology 2; on the other hand, CHO, CHO–Na, and CHNO compounds were distributed in both lithologies. Such different spatial distribution of SOM is likely the result of interaction of the SOM with minerals, during precipitation of the SOM via fluid activity, or could be due to difference in transportation efficiencies of SOMs in aqueous fluid. Organic-related ions measured by time-of-flight secondary ion mass spectrometry (ToF–SIMS) did not coincide with the spatial distribution revealed by DESI-HRMS imaging. This result may be because the different ionization mechanism between DESI and SIMS, or indicate that the ToF–SIMS data would be mainly derived from methanol-insoluble organic matter in A0080. In the Orgueil meteorite, such relationship between altered minerals and SOM distributions was not observed by DESI-HRMS analysis and field-emission scanning electron microscopy, which would result from differences of SOM formation processes and sequent alteration process on the parent bodies or even on the Earth. Alkylated homologues of CHN compounds were identified in A0080 by DESI-HRMS imaging as observed in the Murchison meteorite, but not from the Orgueil meteorite. These compounds with a large C number were enriched in Murchison fragments with abundant carbonate grains. In contrast, such relationship was not observed in A0080, implying different formation or growth mechanisms for the alkylated CHN compounds by interaction with fluid and minerals on the Murchison parent body and asteroid Ryugu.

Ryugu↗

Understanding the Heating Kinetics of Asteroid Ryugu By Comparison to Naturally and Experimentally Heated Meteorites

The Hayabusa2 mission visited the near-Earth Cb-type asteroid (162173) Ryugu and has returned to Earth surface material of Ryugu. Ryugu is an airless rubble pile asteroid exposed to space weathering [1]. Visible and near infrared remote observations recorded an absorption feature at 2.72 μm indicating the presence of OH– bearing hydrous components. The weak 2.72 μm feature suggested that Ryugu was once organic- and water-rich and subsequently dehydrated by a brief period of surficial heating with resemblance to “thermally metamorphosed carbonaceous chondrites”, “CI-/CM-like”, or “CY” chondrites [2, 3]. However, initial examination of the returned samples did not identify any significant heating of >150 °C [4, 5], and contrastingly, amino acid analysis of Ryugu samples suggested similarities to thermally-altered meteorites on the grounds of the predominant straight-chain n-ω-amino acid abundances [6]. In this study, we aim at addressing the nonconformal interpretations to the thermal history of Ryugu by comparing the organic composition of fresh Ryugu samples to that of chondritic meteorites that have been naturally (long-term radiogenic thermal metamorphism and short-term heating) and experimentally heated.

Q. H. S. Chan↗

Comparison of the Bright Boulders on the Surface of the C-Type Asteroid Bennu with White Clasts in the Murchison CM Chondrite Breccia

Spectroscopic observations of asteroid Bennu suggest that the materials on the surface of the asteroid are most similar to aqueously-altered CM- or possibly CI-type carbonaceous chondrites [1], although a relationship with heated CM [2] or CR chondrites [1] is also possible. Recently, [3] detected unusually bright boulders (Fig. 1A) on the surface of Bennu. The band ratio indicates the presence of an absorption feature beyond 0.85μm and is consistent with the presence of mafic minerals such as pyroxene or olivine. The hyperspectral data suggest that the exogenic boulders have the same distinctive pyroxene composition as the howardite-eucrite-diogenite (HED) meteorites. However, similar mineralogical features were also observed in indigenous, thermally metamorphosed white clasts reported in samples of the Murchison CM2 (Fig. 2B; [4-5]) and is an alternative interpretation for the bright boulders observed on Bennu. In addition to detailed petrographic characteristics, we report here further chemistry, O, Cr, and Ti isotopes of the clasts in order to confirm their classification, and discuss their possible relationship to Bennu.

I. Kerraouch↗

Enabling Multiple Small Satellite Near-Earth Asteroid Flyby Missions Using Small Solid Rocket Kick Stages with Rideshare Opportunities

The large number of Near-Earth Asteroids (NEA’s) provide almost daily launch opportunities to send small rideshare spacecraft to explore our nearest neighbors. Most asteroid missions require large spacecraft with a dedicated launch service. The large delta-V required for an interplanetary trajectory would typically preclude a NEA flyby rideshare unless it was going to the same target body as the primary mission. In this paper, a low-cost, compact, high energy kick stage with 3-axissteeringis proposed that would enable this mission type. This kick stage is compatible with an ESPA ring so that multiple NEA missions can be deployed as rideshares on a single launch.

William W Benson↗

Assessing the Oxygen Permeability of Candidate Asteroid Sample Containers With Optochemical Sensors

The Astromaterials Acquisition and Curation Office at NASA Johnson Space Center currently curates 500 mg (10%) of carbonaceous asteroid Ryugu regolith collected by the Japan Aerospace and Exploration Agency’s Hayabusa II spacecraft and returned to Earth in 2021. In September 2023, NASA’s OSIRIS-REx spacecraft returned at least 70 grams of regolith collected from the surface of Carbonaceous Asteroid Bennu. These new astromaterials collections are stored and handled in gloveboxes and desiccators that are continuously purged with ultrapure nitrogen in order to minimize contamination and alteration of extraterrestrial samples from terrestrial environments, e.g., reaction with terrestrial oxygen and water. Ito et al. have previously reported on the development of containers to transport samples between facilities in inert, sealed environments; Hayabusa2 samples allocated to investigators by JAXA’s Extraterrestrial Sample Curation Center (ESCuC) are shipped in these Facility-to-Facility Transfer Containers (FFTCs). NASA curation has also been investigating sealed containers for storage, transportation, and allocation of Bennu and Ryugu regolith in sealed anoxic environments. In order to assess the ability of candidate sample containers to maintain nitrogen environments, we have utilized optochemical sensors to measure trace oxygen levels within sealed volumes.

C J Snead↗

Carbon and Nitrogen Abundance, Distribution, and Isotopic Composition in Samples of Asteroid (101955) Bennu

Material from the B-type carbonaceous asteroid (101955) Bennu was returned on September 24, 2023, by NASA’s OSIRIS-REx mission. The mission brought back the largest sample of pristine primordial asteroidal material, largely free from the challenges of terrestrial contamination that are common in meteorite studies. The Bennu sample thus provides a unique source of material to investigate the abundance and isotopic signatures of C and N. The specific hypotheses tested by these analyses are whether Bennu contains macromolecular material and/or presolar grains similar to the populations found in CI and CM chondrites and recently returned samples from Ryugu.

M. M. Grady↗

Noble Gases in Individual Particles From Bennu: Investigating the Origin of Gas-Rich Asteroidal Material

One of the driving hypotheses of the OSIRIS-REx mission [1] is that B-type asteroid Bennu formed beyond the snow line by accretion of material of the protoplanetary disk. Hence Bennu is expected to be rich in highly volatile elements. Among them, noble gases are chemically inert and their abundances and isotope compositions are shaped by physical processes such as radioactivity, irradiation, and isotope fractionation [2]. Hence studying the noble gas composition of Bennu's grains can contribute to testing Hypotheses 4 (formation beyond the snow line), 5 (geological activity), and 6 (catastrophic disruption) of the OSIRIS-REx mission [1]. Here we report preliminary data obtained on particles from asteroid Bennu using our all-noble-gas (He to Xe) analytical system installed at the Centre de Recherches Pétrographiques et Géochimiques (CRPG) Nancy (France) [3]. A companion presentation presents nitrogen-Ne-Ar data [4].

B. Marty↗

Surface Exposure History of Asteroid Bennu Based on Cosmogenic Radionuclides in OSIRIS-Rex Samples

The surface of asteroid Bennu changes over time because of impacts, mass movement, and particle ejections [1-4]. The OSIRIS-REx samples were collected from a 20-m-diameter crater on Bennu called Hokioi. One of the driving hypotheses of the mission is that Hokioi is part of a population of small (<25 m) craters that are less than 0.1 Myr old and contain relatively unweathered material [1,4]. Our goal is to understand the recent surface exposure history of Bennu, utilizing radionuclides (10Be, 26Al, 36Cl, 41Ca) produced by both galactic and solar cosmic rays. We received ~12 mg of aggregate sample OREX-803014-0. We picked five of the larger particles with masses ranging from 0.24 to 0.68 mg. We dissolved each particle, along with 0.15 mg Be and 1.0 mg Cl carrier, in HF/HNO3 mixture, and did the same for the remaining aggregate sample of 9.8 mg. After dissolution, we took a small aliquot for chemical analysis, added 0.7 mg of Al carrier, and separated Be, Al, and Cl for analysis of cosmogenic 10Be, 26Al, and 36Cl by accelerator mass spectrometry [5]. Preliminary 26Al results show concentrations of 21–27 dpm/kg for the Bennu samples, with an average of 22.5 ± 0.6 dpm/kg for the five particles and 21.1 ± 0.7 dpm/kg for the remaining aggregate. These values are close to the expected 26Al saturation values of 25–30 dpm/kg for the top 1 m of Bennu’s regolith, suggesting a minimum exposure age of 1.5–2.0 Myr near the surface. Our initial Bennu results also resemble those found for Ryugu samples [6,7]; thus, we can hypothesize that the two asteroids have had similar surface exposure histories.

K C Welten↗