Solar System Research, Год журнала: 2024, Номер 58(S1), С. S30 - S39
Опубликована: Ноя. 21, 2024
Язык: Английский
Nature Astronomy, Год журнала: 2024, Номер unknown
Опубликована: Май 22, 2024
Язык: Английский
Процитировано
13
Icarus, Год журнала: 2024, Номер 412, С. 115999 - 115999
Опубликована: Фев. 8, 2024
Язык: Английский
Процитировано
12
The Planetary Science Journal, Год журнала: 2024, Номер 5(4), С. 87 - 87
Опубликована: Апрель 1, 2024
Abstract We present observations obtained with the Near Infrared Spectrograph on JWST of five Jupiter Trojans that will be visited by Lucy spacecraft—the Patroclus–Menoetius binary, Eurybates, Orus, Leucus, and Polymele. The measured 1.7–5.3 μ m reflectance spectra, which provide increased wavelength coverage, spatial resolution, signal-to-noise ratio over previous ground-based spectroscopy, reveal several distinct absorption features. detect a broad OH band centered at 3 is most prominent less-red objects Patroclus–Menoetius, An additional feature 3.3–3.6 m, indicative aliphatic organics, systematically deeper red Orus Leucus. collisional fragment Eurybates unique in displaying an 4.25 we attribute to bound or trapped CO 2 . Comparisons other solar system small bodies similarities 2.7–3.6 bands analogous features Centaurs, Kuiper Belt (KBOs), active asteroid 238P. In context recent evolution models, posit initially formed outer system, significant attenuation relative KBOs may result secondary thermal processing Trojans’ surfaces higher temperatures region. manifested surface suggests major constituent bulk composition Trojans, but resides subsurface interior largely obscured refractory material from thermophysical processes were activated during their inward migration.
Язык: Английский
Процитировано
11
The Astrophysical Journal Letters, Год журнала: 2024, Номер 970(2), С. L29 - L29
Опубликована: Июль 24, 2024
Abstract The Uranian moon Ariel exhibits a diversity of geologically young landforms, with surface composition rich in CO 2 ice. origin and other species, however, remains uncertain. We report observations Ariel’s leading trailing hemispheres, collected NIRSpec (2.87–5.10 μ m) on the James Webb Space Telescope. These data shed new light Ariel's spectral properties, revealing double-lobed ice scattering peak centered near 4.20 4.25 m, m lobe possibly representing largest Fresnel yet observed solar system. A prominent 4.38 13 feature is also present, as 4.90 band that results from 12 spectra reveal 4.67 broad 4.02 might result carbonate minerals. confirm features associated are notably stronger hemisphere compared to its hemisphere. detected synthetic mixtures CO, H O, amorphous carbon, finding could be concentrated deposits thicker than ∼10 mm Comparison laboratory indicates likely mixed . evidence for thick possible presence carbonates both hemispheres suggests some carbon oxides sourced interior, their distributions modified by charged particle bombardment, sublimation, seasonal migration high low latitudes.
Язык: Английский
Процитировано
7
Astronomy and Astrophysics, Год журнала: 2025, Номер 694, С. A126 - A126
Опубликована: Янв. 16, 2025
Context . The James Webb Space Telescope large program DiSCo-TNOs has recently shown that CO 2 ice is ubiquitous on 54 mediumsize trans-Neptunian objects (TNOs). TNO surfaces are found to define three main spectral and thus compositional groups likely linked their position before planetary migration. observed the type richest in richer CH 3 OH organics. Considerations thermal evolution of TNOs predicted depletion hypervolatiles such as from surface layers, however. Aims We investigate a potential irradiation origin well its stability by studying distribution two types compared it with experiments. Methods studied 4.68 µm band 2.70 probe relation between molecules 33 TNOs. performed ion experiments ices at 45 60 K 30 keV H + laboratory spectra observations focusing areas positions. Results find which detected very distinct terms relative abundances chemical environment. rich consistent being produced irradiation, specifically, K. On complex organics, more formed OH. As only partly related temperature, environment plays major role retention. Conclusions compatible secondary molecule entirely late processes. Its abundance mostly controlled matrix formed.
Язык: Английский
Процитировано
1
The Planetary Science Journal, Год журнала: 2024, Номер 5(3), С. 60 - 60
Опубликована: Март 1, 2024
Abstract We analyzed spectral cubes of Callisto’s leading and trailing hemispheres, collected with the NIRSpec Integrated Field Unit (G395H) on James Webb Space Telescope. These spatially resolved data show strong 4.25 μ m absorption bands resulting from solid-state 12 CO 2 , strongest features at low latitudes near center its hemisphere, consistent radiolytic production spurred by magnetospheric plasma interacting native H O mixed carbonaceous compounds. detected rovibrational emission lines between 4.2 4.3 over both confirming global presence gas in tenuous atmosphere. results represent first detection side. The distribution is offset subsolar region either suggesting that sputtering, radiolysis, geologic processes help sustain a 4.38 band likely 13 . A prominent 4.57 might result CN-bearing organics present significantly stronger unlike these two are antiassociated. more origin and/or accumulation dust Jupiter’s irregular satellites. Other, subtle could CH-bearing organics, CO, carbonyl sulfide, Na-bearing minerals. highlight need for preparatory laboratory work improved surface–atmosphere interaction models to better understand carbon chemistry icy Galilean moons before arrival NASA’s Europa Clipper ESA’s JUICE spacecraft.
Язык: Английский
Процитировано
5
The Astrophysical Journal, Год журнала: 2024, Номер 976(1), С. 14 - 14
Опубликована: Ноя. 1, 2024
Abstract We examine the role of refractory organics as a major C carrier in outer protosolar nebula and its implications for compositions large Kuiper Belt objects (KBOs) CI chondrites. By utilizing Rosetta measurements comet 67P/Churyumov–Gerasimenko, we show that they would make up fraction inventory KBO-forming region based on current widely adopted solar abundances. However, this free too much O to form water ice, producing solid material is not sufficiently rock-rich explain uncompressed density Pluto–Charon system other KBOs; former has been argued most representative value have bulk composition KBOs. This inconsistency further highlights abundances problem—an ongoing challenge reconciling spectroscopically determined heavy-element with helioseismology constraints. employing new data set from CNO neutrinos wind C, N, O, can be reproduced over wide range scenarios. lack sulfates Ryugu Bennu samples implies lower amount ice initially accreted into chondrite parent bodies than previously thought. These are found consistent C/O ratio implied by set. Our predictions tested future neutrino, helioseismology, cosmochemical measurements.
Язык: Английский
Процитировано
5
The Astrophysical Journal Letters, Год журнала: 2024, Номер 976(1), С. L9 - L9
Опубликована: Ноя. 1, 2024
Abstract We report on the discovery of a very prominent mid-infrared (18–25 μ m) excess associated with trans-Neptunian dwarf planet (136472) Makemake. The excess, detected by Mid-Infrared Instrument James Webb Space Telescope, along previous measurements from Spitzer and Herschel space telescopes, indicates occurrence temperatures ∼150 K, much higher than what solid surfaces at Makemake’s heliocentric distance could reach solar irradiation. identify two potential explanations: continuously visible, currently active region powered subsurface upwelling possibly cryovolcanic activity covering ≤1% surface or an as-yet-undetected ring containing small carbonaceous dust grains, which have not been seen before in Centaur rings. Both scenarios point to unprecedented phenomena among objects greatly impact our understanding these distant worlds.
Язык: Английский
Процитировано
3
The Planetary Science Journal, Год журнала: 2025, Номер 6(1), С. 9 - 9
Опубликована: Янв. 1, 2025
Abstract We present JWST Near Infrared Spectrograph (NIRSpec) measurements of the three largest low-albedo main-belt asteroids: (1) Ceres, (2) Pallas, and (10) Hygiea. Their reflectance spectra all have very similar absorptions centered near 2.72 μ m attributed to Mg–OH in minerals. Within this band, Pallas also shows evidence a sharper, deeper m. These band positions are those seen most aqueously altered carbonaceous chondrites samples from Ryugu Bennu. Absorptions 2.7–2.9 region due other cation–OH combinations weak, if present. The NIRSpec spectrum Ceres is consistent with global average Dawn, similarity between Hygiea wavelength regions continues into 2.5–2.8 region. This spectral properties, thus interpretations surface composition, implies that two bodies may had processes occur histories. suggests Hygiea, be associated “ocean worlds” despite its relatively small mass. Quantitative estimates hydrogen concentrations on surfaces suggest roughly 0.5–1 wt%, CM chondrites. Additional ammoniated minerals Ceres’s Hygiea’s spectra, as has been reported by others, but not Pallas’s spectrum. 2.5–2.7 asteroids, likely OH combination bands, 3.9 4.3 which could carbonates plus an unidentified constituent.
Язык: Английский
Процитировано
0
Monthly Notices of the Royal Astronomical Society Letters, Год журнала: 2025, Номер unknown
Опубликована: Янв. 13, 2025
Abstract Eris, one of the five official dwarf planets, is slightly smaller than Pluto and notable for its high geometric albedo homogeneous surface, which has hindered a clear determination rotation period. Recently, it was shown that Eris tidally locked to 15.786-day orbit satellite, Dysnomia. Our analysis Eris’ Gaia DR3 photometry reveals strong periodicity peak at 18.852 ± 0.003 hours, most prominent in Lomb-Scargle periodogram, with stronger signal 15.77 0.02-day period also present data. We analyzed whether newly identified could be an artifact, but found no reason other phenomenon Eris. Since Dysnomia too faint account photometric variability, potential explanation either periodicities presence unknown close-in satellite. An additional undetectable so far by HST, explain Dysnomias non-Keplerian lower Eriss density ∼ 2000 kg/m3, consistent similar-sized TNOs Triton. It would decrease ∼10%, aligning more closely expected values. However, this possibility considerable problems, scenarios are explored.
Язык: Английский
Процитировано
0