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The aim of this work is to characterize, from a thermophysical perspective, the dark resistant unit (DRU) characterizing Germania Lacus in the Oxia Planum Region, providing new insights to constrain the nature of the materials which compose this unit. We investigated the temperature distribution of the DRU by adopting common values of the thermophysical parameters of the basalt and by exploring several values of porosity. As an additional case, we also explore a composition made of pebbles. The numerical model developed here represents a follow-up of the work recently published by Formisano et al. 2021, and it takes into account a large-scale topography of the site and assumes a diurnal temperature profile for the atmosphere rather than a constant value (unlike Formisano et al. 2021). Comparisons with Mars Pathfinder and Viking data as well as numerical models are also reported. The methodology described here could be useful to characterize as well other sites on Mars’ surface with available small-scale topographic data.

Abstract We propose a new internal evolution model for the dwarf planet Ceres matching the constraints on Ceres' present internal state from the Dawn mission observations. We assume an interior differentiated into a volatile‐dominated crust and rocky mantle, and with remnant brines in the mantle, all consistent with inferences from the Dawn geophysical observations. Simulations indicate Ceres should preserve a warm crust until present if the crust is rich in clathrate hydrates. The temperature computed at the base of the crust exceeds 220 K for a broad range of conditions, allowing for the preservation of a small amount of brines at the base of the crust. However, a temperature ≥250 K, for which at least 1 wt.% sodium carbonate gets in solution requires a crustal abundance of clathrate hydrates greater than 55 vol.%, a situation possible for a narrow set of evolutionary scenarios.

Numerical simulations are required to thermophysically characterize Oxia Planum, the landing site of the mission ExoMars 2022. A drilling system is installed on the ExoMars rover, and it will be able to analyze down to 2 meters in the subsurface of Mars. The spectrometer Ma_MISS (Mars Multispectral Imager for Subsurface, Coradini and Da Pieve, 2001) will investigate the lateral wall of the borehole generated by the drill, providing hyperspectral images. It is not fully clear if water ice can be found in the subsurface at Oxia Planum. However, Ma_MISS has the capability to characterize and map the presence of possible ices, in particular water ice. We performed simulations of the subsurface temperatures by varying the thermal inertia, and we quantified the effects of self-heating. Moreover, we quantified the heat released by the drilling operations, by exploring different frictional coefficients and angular drill velocities, in order to evaluate the lifetime of possible water ice.

Purpose: This study aims to assess retinal vascular changes following internal limiting membrane (ILM) peeling for idiopathic epiretinal membrane (ERM) treatment using optical coherence tomography angiography (OCT-A)., Design: A retrospective study was conducted., Methods: A cohort of thirty-nine patients was enlisted for this study. Each participant underwent comprehensive ophthalmological evaluation and OCT-A imaging at baseline, as well as at 1-month and 6-month intervals post-pars plana vitrectomy with ERM and ILM peeling., Results: Post-surgery, remarkable improvements were observed in best-corrected visual acuity (BCVA) (from 0.335 ± 0.173 to 0.096 ± 0.126 at 6 months), coupled with a notable reduction in central retinal thickness (CRT) (from 460 ± 87 µm to 395 ± 53 µm at 6 months). Additionally, there was a noticeable expansion in the foveal avascular zone (FAZ) perimeter (from 0.099 ± 0.060 mm² to 0.125 ± 0.056 mm² at 6 months). However, there was a decline in vessel density (VD) in the superficial capillary plexus (SCP) (from 46.7 ± 4.4 to 43.8 ± 3.5% at 6 months), contrasted by an elevation in the deep capillary plexus (DCP) (from 45.2 ± 5.5% to 43.6 ± 5.3% at 6 months. Noteworthy correlations were detected between CRT and BCVA, as well as CRT and vascular parameters., Conclusion: ERM instigates a milieu of changes including SCP crowding and elevation, potentially leading to a falsely augmented density at OCT-A in affected patients. Subsequent surgery results in a release of ERM-induced forces, elucidating the observed decrease in SCP density. Conversely, the DCP appears to be less distorted by the ERM, facilitating gradual vessel reopening after its removal. OCTA provides valuable insights into optimal surgical timing., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Purpose: To compare the surgical and clinical outcomes of 27-gauge vitrectomy and 23-gauge vitrectomy., Methods: We conducted a single-center, prospective, randomized study. Fifty-three patients affected by vitreoretinal interface disorders (epiretinal membranes and macular holes) were randomly scheduled to undergo 27-gauge (28 patients) or 23-gauge (25 patients) pars plana vitrectomy. The presence of any potential factor of increased baseline inflammation or eye anatomy influencing the surgery was criteria for exclusion. The time of surgery, postoperative intraocular pressure (IOP), state of sclerotomy wounds, rate of complications, postoperative pain, and indicators of inflammation were studied. We also introduced a new parameter to compare intraocular inflammation after surgery, given by the change in the number of intraretinal hyperreflective foci (HRF)., Results: The 27-gauge vitrectomy was 1.28 min longer than 23-gauge vitrectomy ( P < 0.05). The day after surgery, the mean IOP value was significantly higher in the 27-gauge group (16.12 mmHg versus 13.04 mmHg in the 23-gauge group, P < 0.05), but this difference disappeared in successive follow-ups and the sclerotomy wounds closed after 2 weeks in the both groups. The rate of postoperative hypotony did not significantly differ in the two groups (10.71% in the 27-gauge group and 8% in the 23-gauge group the day after the surgery, P = 0.94). Less postoperative eye redness was seen in 27-gauge eyes (value 1 on the scale) compared to 23-gauge (value 2 on the scale) ( P < 0.05), but there was no significant difference in intraocular inflammation (cells, Tyndall, and number of HRF, P > 0.05 for all)., Conclusions: The 27-gauge vitrectomy may have better outcomes in terms of IOP maintenance and cause less redness after the surgery but with a slightly prolonged surgery time and no other differences under other parameters (inflammation, rate of complications, postoperative pain, visual gain, and closure of the sclerotomy wounds)., Competing Interests: There are no conflicts of interest., (Copyright: © 2024 Journal of Current Ophthalmology.)

The Ma&#95;MISS miniaturized spectrometer is integrated within the Drilling System of the ExoMars Rosalind Franklin Rover for Mars exploration. Here we focus on the on ground calibration campaign to obtain radiometric and linearity calibrations of the Ma&#95;MISS instrument, while the first paper dealt with the spectral calibration [De Angelis et al., Rev. Sci. Instrum. 93, 123704 (2022)]. The experimental setup used to carry out radiometric calibration is described, as are the methods used for data processing and key parameter retrieval. In particular, the Spectrometer Transfer Function (Responsivity), Signal-to-Noise Ratio, and detector linearity are determined. In a third paper [De Sanctis et al., Planet. Sci. J. 3, 142 (2022)], validation of the Ma&#95;MISS calibration results through spectral measurements performed on rock and synthetic targets during the radiometric calibration campaign is described., (© 2023 Author(s). Published under an exclusive license by AIP Publishing.)

Stargardt disease is the commonest juvenile macular dystrophy. It is caused by genetic mutations in the ABCA4 gene. Diagnosis is not always straightforward, and various phenocopies exist. Late-onset disease can be misdiagnosed with age-related macular disease. A correct diagnosis is particularly critical because of emergent gene therapies. Stargardt disease is known to affect retinal pigment epithelium and photoreceptors. Many studies have also highlighted the importance of the choroid in the diagnosis, pathophysiology, and progression of the disease. The choroid is in an integral relationship with the retinal pigment epithelium and photoreceptors, and its possible involvement during the disease should be considered. The purpose of this review is to analyze the current diagnostic tools for choroidal evaluation and the extrapolation of useful data for ophthalmologists and researchers studying the disease.

Hereditary haemorrhagic telangiectasia (HHT) or Osler-Rendu-Weber syndrome is a rare autosomal dominant disease, characterised by systemic angiodysplasia. Dysfunction of the signalling pathway of β transforming growth factor is the main cause of HHT principally owing to mutations of the genes encoding for endoglin (ENG) and activin A receptor type II-like 1 (ACVRL1). Clinical manifestations can range from mucocutaneous telangiectasia to organ arterio-venous malformations and recurrent epistaxis. The early clinical manifestations may sometimes be subtle, and diagnosis may be delayed. The main ophthalmic manifestations historically reported in HHT are haemorrhagic epiphora, and conjunctival telangiectasia present in 45-65% of cases, however, imaging with wide-field fluorescein angiography has recently shown peripheral retinal telangiectasia in 83% of patients. Optimal management of HHT requires both understanding of the clinical presentations and detection of early signs of disease. Advances in imaging methods in ophthalmology such as wide-field fluorescein angiography, spectral domain optical coherence tomography, and near infrared reflectance promise further insight into the ophthalmic signs of HHT towards improved diagnosis and early management of possible severe complications., (© 2022. The Author(s).)

Abstract: The cardinal diagnostic signs of neurofibromatosis type 1 (NF1) are Lisch nodules of the iris and optic pathway gliomas. Retinal mi-crovascular alterations have been described but with uncertain signi-ficance. Choroidal nodules, detectable with near-infrared reflectance (NIR) imaging, are present in most cases and have been proposed as a new diagnostic criterion. Recently, a study reported the presence of unusual dilated choroidal vessels, visible through NIR examination. We report a case of a 65-year-old patient with NF1. Best-corrected visual acuity was 20/20 with a refractive error of +2.75 diopters in both eyes. Anterior segment examination revealed Lisch nodules in both eyes. At NIR imaging the patient presented typical choroidal alterations in both eyes. No retinal vessel anomalies were detected. The patient presented enlarged choroidal vessels in the left eye, first detected by NIR and then analyzed through enhanced depth imaging spectral domain optical coherence tomography (EDI-SDOCT). These vessels extended from the choroidal-scleral junction to the outer border of the retinal pigment epithelium/Bruch's layer. The choriocapillaris layer was absent above the dilated vessels. The presence of enlarged choroidal vessels may be considered as a novel distinctive ophthalmologic aspect of NF1, but further studies are necessary.

Purpose: Patients affected by severe atresia auris (AA) can be a challenge during hearing restoration surgery due to the abnormal position of vascular and nervous structures in the bone. A 3D reconstruction model of malformed temporal bones can be helpful for planning surgery and optimizing intra-, peri-, and post-operative results., Method: A 5-year-old girl with severe AA on the right side was implanted with a Bonebridge transcutaneous bone conduction implant (tBCI). 3D printing was used to reproduce the malformed temporal bone, find a good position for the tBCI and plan out the surgical details in advance. Hearing tests were performed before and after surgery and information about intra-, peri-, and post-operative outcomes were collected., Results: The patient did not show any negative outcomes and, thanks to the Bonebridge, completely recovered hearing on the right side., Conclusions: 3D printing is a useful tool for planning surgery in AA patients and for preventing possible risks related to the unknown malformed anatomy., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.)

Background : Diffuse choroidal hemangioma (DCH) is a benign vascular tumor that is characteristically found in the Sturge-Weber syndrome (SWS). Recent genetic discoveries demonstrate that DCH occurs sporadically from an activating mutation in GNAQ at codon R183 . Mutations in GNAQ or GNA11 result in dysregulation of the mitogen-activated protein kinase, which influences gene transcription and results in cellular proliferation. DCH may not always be readily detected on routine ophthalmological examination, consequently diagnosis and multidisciplinary referral are often delayed. Purpose : A literature search was performed through April 2020 without a lower date limit. This review will summarize the pathogenesis, diagnosis and management of DCH. Discussion : Multimodal imaging facilitates early detection of the condition. In particular, enhanced depth imaging spectral domain optical coherence tomography enables non-invasive, high-resolution visualization of the choroid to even detect mild choroidal thickening. Management of symptomatic DCH is generally difficult and results in poor visual outcome, thus, treatment is generally unwarranted, unless the hemangioma complicated by serous retinal detachment. The main treatment method is radiation therapy with external beam radiation therapy, proton beam therapy, plaque brachytherapy, and gamma knife surgery where low doses of radiation entail fewer complications. One method of alternative management is with photodynamic therapy that, although less invasive with a lower rate of complications, is not always feasible or effective in cases with extensive exudative retinal detachment. Conclusions: Multimodal ophthalmological imaging facilitates diagnosis of DCH and lifelong surveillance is essential in patients.

Purpose: The aim of the present study was to evaluate the visual outcome of a new extended depth-of-focus (EDOF) intraocular lens (IOL) after bilateral implantation. A qualitative and quantitative analysis was performed and data were compared with those given by other studies regarding multifocal IOLs, which have the same purpose of giving spectacle independence to the patients., Methods: The study enrolled 40 eyes of 20 patients who underwent cataract surgery with bilateral implantation of an EDOF IOL (Evolve Soleko, Rome, Italy). The mean age was 74.5±9 years (range 59-83ys). Refractive outcomes and contrast sensitivity were evaluated preoperatively and at 6-month follow-up. We also examined reading speed, glare, halos, difficulties in the night driving, the requirement for spectacles, and overall satisfaction with vision. Two questionnaires were administered for this purpose., Results: At 6 months, the percentage of eyes within ±0.50 diopters (D) from emmetropia was 82.5%. Of all patients, 90% were satisfied with their vision. The percentage of spectacle-free for near and distance vision patients was 70% and 95%, respectively. A postoperative binocular uncorrected 60cm intermediate visual acuity (UI60VA) of 0.2 logMAR or better was achieved in 92% of patients. Contrast sensitivity significantly improved postoperatively (p<0.001) and mean reading speed was good., Conclusion: This new EDOF IOL seems to provide an effective alternative to patients who desire a spectacle-free lifestyle postoperatively. These lenses can supply a satisfactory distance, intermediate and near vision, and retain good contrast sensitivity, with most patients reporting excellent satisfaction., Competing Interests: The authors report no conflicts of interest in this work., (© 2021 Spadea et al.)

Background : Retinal astrocytic hamartoma (RAH) is a tumor that can be sporadic or in the context of tuberous sclerosis complex (TSC) and has been reported to be associated with neurofibromatosis type 1 (NF1) in a few cases. Patient and methods : A 65-year-old male patient with NF1 was referred for ophthalmological evaluation. Comprehensive examination, near-infrared reflectance (NIR), spectral-domain optical coherence tomography (SDOCT), fluorescein angiography (FFA), and indocyanine green angiography (ICGA) were carried out. The follow-up of the patient was at 4 and 7 years. Results : Best-corrected visual acuity (BCVA) was 20/20 in both eyes. Anterior segment examination revealed bilateral Lisch nodules. Fundus examination was unremarkable but at NIR and SDOCT the patient presented choroidal hamartoma, microvascular retinal alterations, and enlarged choroidal vessels in both eyes. NIR also revealed an unusual area of peripapillary hyporeflectivity in the right eye. On SDOCT, this corresponded to an elevated peripapillary mass characterized by intralesional optically empty cavities in the retinal nerve fiber layer (RNFL) and ganglion cell layer-inner plexiform layer (GCL-IPL), diagnosed as a RAH. Four years later, BCVA was 20/25 with a retinal schisis departing from the lesion to the macula. At 7 years, BCVA was stable at 20/25, the lesion was smaller, and there was a slight reduction of the schisis. Conclusion : RAH is a rare finding in NF1 and the translucent type has not been previously reported. RAH in NF1 has a peripapillary location and demonstrates clinically unpredictable behavior; thus, close monitoring with multimodal imaging is advisable.

Purpose: To evaluate the visual acuity level achieved by scleral contact lens (CL) fitting in patients affected by keratoconus and to evaluate possible intraocular pressure (IOP) changes during the scleral CL wear using a transpalpebral tonometer., Methods: In a prospective case series a comparison was made between visual acuity obtained with glasses, RGP and 16.8mm diameter scleral CL in 30 consecutive patients affected by keratoconus. IOP was tested during scleral CL wear by transpalpebral Diaton Tonometer (DT) and also by Goldmann Applanation Tonometer (GAT) before and after scleral CL wear., Results: The mean logMAR visual acuity improved from 0.2±0.25SD with glasses and 0.1±0.02SD with RGP, to -0.002±0.041SD when using the scleral CL ( p <0.05). The mean IOP value before scleral CL wear was 12.93mmHg±2.20SD when measured with GAT and 7.85mmHg±2.27SD when measured with DT. During scleral CL wear, IOP was assessed through DT, with a mean value of 8.86mmHg±2.36SD; values were stable after 8 hours of scleral CL use. Immediately after scleral CL removal, the mean IOP measured with GAT was 12.85mmHg ±2.40SD and the mean IOP measured with DT was 7.66mmHg±1.88SD. Therefore, during scleral CL wear, it was evidenced a small but statistically significant increase of the mean IOP value (1.01mmHg; p <0.01), with a reversion to values prior to application when scleral CL was removed., Conclusion: Scleral CLs remarkably improved visual acuity in keratoconus patients when compared to glasses or RGP contact lenses. Even if it was evidenced a small increase of the mean IOP value during their wear, it may not be significant in otherwise healthy eyes. Statistical analysis demonstrated good agreement between GAT and DT but their numerical values presented a constant gap, that should be taken into account when there is a need to relate the DT values to the reference ones., Competing Interests: The authors report no conflicts of interest in this work., (© 2021 Formisano et al.)

The NASA/Dawn mission has acquired unprecedented measurements of the surface of the dwarf planet Ceres, the composition of which is a mixture of ultra-carbonaceous material, phyllosilicates, carbonates, organics, Fe-oxides, and volatiles as determined by remote sensing instruments including the VIR imaging spectrometer. We performed a refined analysis merging visible and infrared observations of Ceres' surface for the first time. The overall shape of the combined spectrum suggests another type of silicate not previously considered, and we confirmed a large abundance of carbon material. More importantly, by analyzing the local spectra of the organic-rich region of the Ernutet crater, we identified a reddening in the visible range, strongly correlated to the aliphatic signature at 3.4 µm. Similar reddening was found in the bright material making up Cerealia Facula in the Occator crater. This implies that organic material might be present in the source of the faculae, where brines and organics are mixed in an environment that may be favorable for prebiotic chemistry.

Indolent, non-progressive choroidal alterations can be strongly suggestive of neurofibromatosis type 1 (NF1) but are also rarely of unknown aetiology. A 63-year-old man presented for a routine examination. Comprehensive ophthalmological examination and retinal imaging was performed. Visual acuity was 20/20. The anterior segment and fundus were unremarkable. Near-infrared reflectance (NIR) with spectral-domain optical coherence tomography showed unilateral hyperreflective areas in the left posterior pole, corresponding to choroidal nodules on enhanced depth imaging and hypofluorescent areas on indocyanine green angiography. Dermatological evaluation and genetic testing for NF1 were negative. Chest computed tomography, liver function, HLA-A29, and angiotensin-converting enzyme level were negative. The patient has remained in good health and the choroidal alterations have remained non-progressive for 3 years. Choroidal alterations observed with NIR could be a manifestation of somatic mosaicism or a variation of a new unclassified correlated condition that may be better elucidated in the future, given the use of novel imaging techniques that are currently available in ophthalmology., Competing Interests: The authors have no conflicts of interest to declare., (Copyright © 2020 by S. Karger AG, Basel.)

Solar heating of a cometary surface provides the energy necessary to sustain gaseous activity, through which dust is removed 1,2 . In this dynamical environment, both the coma 3,4 and the nucleus 5,6 evolve during the orbit, changing their physical and compositional properties. The environment around an active nucleus is populated by dust grains with complex and variegated shapes 7 , lifted and diffused by gases freed from the sublimation of surface ices 8,9 . The visible colour of dust particles is highly variable: carbonaceous organic material-rich grains 10 appear red while magnesium silicate-rich 11,12 and water-ice-rich 13,14 grains appear blue, with some dependence on grain size distribution, viewing geometry, activity level and comet family type. We know that local colour changes are associated with grain size variations, such as in the bluer jets made of submicrometre grains on comet Hale-Bopp 15 or in the fragmented grains in the coma 16 of C/1999 S4 (LINEAR). Apart from grain size, composition also influences the coma's colour response, because transparent volatiles can introduce a substantial blueing in scattered light, as observed in the dust particles ejected after the collision of the Deep Impact probe with comet 9P/Tempel 1 17 . Here we report observations of two opposite seasonal colour cycles in the coma and on the surface of comet 67P/Churyumov-Gerasimenko through its perihelion passage 18 . Spectral analysis indicates an enrichment of submicrometre grains made of organic material and amorphous carbon in the coma, causing reddening during the passage. At the same time, the progressive removal of dust from the nucleus causes the exposure of more pristine and bluish icy layers on the surface. Far from the Sun, we find that the abundance of water ice on the nucleus is reduced owing to redeposition of dust and dehydration of the surface layer while the coma becomes less red.

Purpose : To assess macular ganglion cell layer (GCL) thickness in patients treated with intravitreal anti-vascular endothelial growth factor (anti-VEGF) for exudative age-related macular degeneration (AMD). Materials and Methods : This was a two-year retrospective institutional case series where records of patients treated with anti-VEGF injections for unilateral AMD were reviewed for BCVA, intraocular pressure, and spectral domain optical coherence tomography. Macular GCL thickness was evaluated with automated retinal segmentation based on ETDRS grid rings. Retinal layer segmentation was carefully assessed and manually corrected for any misalignment. Results : 48 eyes of 24 patients with unilateral exudative AMD were included. The mean number of anti-VEGF injections was 10.4 ± 3.2. Fellow eyes were classified as AREDS category one and two. There was significant thinning of the 3-mm macular GCL in treated compared with fellow eyes at one and two years (P = .03 and P = .04, respectively). GCL thickness compared to baseline showed a significant decrease at one and two years in treated (P = .01 and <0.0001) and at two years in untreated fellow eyes (P = .02). Conclusions : There is a decrease of macular GCL thickness in eyes with exudative AMD treated with anti-VEGF intravitreal injections in comparison with fellow eyes. There is longitudinal thinning of the GCL from baseline in eyes with both treated exudative and non-treated early AMD.

Purpose: To present a patient with bilateral choroidal hemangioma in Sturge-Weber syndrome (SWS) and highlight multimodal imaging techniques for early detection and management of ocular alterations., Methods: A 37-year-old woman with diagnosis of SWS presented to our unit. The patient had been treated with pulsed dye laser for bilateral nevus flammeus and had right leptomeningeal angiomatosis. She had glaucoma, but ultrasound biomicroscopy did not show anterior chamber or ciliary body alterations., Results: Enhanced depth imaging (EDI) spectral domain optical coherence tomography (SD-OCT) showed bilateral diffuse choroidal hemangiomas in both eyes with choroidal thickness above 1000 μm. B-scan ultrasound examination showed diffuse choroidal hemangioma in both eyes, with a choroidal thickness of 1.53 mm and 1.94 mm in the right and left eye (RE, LE), respectively. Peripapillary retinal nerve fiber evaluation showed thinning of the retinal nerve fiber layer in both eyes., Conclusions: This report highlights multimodal imaging techniques for the critical assessment of patients with SWS, especially in rare cases with bilateral choroidal hemangioma of the choroid. Novel imaging modalities enable optimal management and follow-up of rare conditions, and our case adds further evidence to the existing literature.

Water absorption bands due to superficially adsorbed molecules often dominate the near-infrared spectra of particulate minerals and rocks, when measured in the laboratory in the reflectance mode. In order to remove this, the spectral effect is thus necessary to acquire spectra of samples in vacuum and at higher temperatures. With the aim to accomplish this task, we developed an environmental cell to perform infrared spectroscopic measurements at controlled pressure-temperature conditions. Currently the cell allows one to measure reflectance spectra in the temperature range from room values up to 300 °C (573 K), in the pressure range of 10 3 -10 -6 mbar. The acquisition of spectra continuously in two distinct phases, namely, during a preliminary pumping stage (at room T) and subsequently during a heating stage (in vacuum), permits to highlight and characterize separately the effect of pressure and temperature on infrared spectra.

Different carbonates have been detected on Ceres, and their abundance and spatial distribution have been mapped using a visible and infrared mapping spectrometer (VIR), the Dawn imaging spectrometer. Carbonates are abundant and ubiquitous across the surface, but variations in the strength and position of infrared spectral absorptions indicate variations in the composition and amount of these minerals. Mg-Ca carbonates are detected all over the surface, but localized areas show Na carbonates, such as natrite (Na 2 CO 3 ) and hydrated Na carbonates (for example, Na 2 CO 3 ·H 2 O). Their geological settings and accessory NH 4 -bearing phases suggest the upwelling, excavation, and exposure of salts formed from Na-CO 3 -NH 4 -Cl brine solutions at multiple locations across the planet. The presence of the hydrated carbonates indicates that their formation/exposure on Ceres' surface is geologically recent and dehydration to the anhydrous form (Na 2 CO 3 ) is ongoing, implying a still-evolving body.