Modeling the thermal environment of Mercury’s north pole using MLA. Implications for locations of water ice

Gläser, P.; Oberst, J.

doi:10.1016/j.icarus.2022.115349

Cited by 2 publications

(6 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our new higher-resolution thermal models for these four northernmost craters show extensive regions within them where surface water ice can be stable, consistent with the lower-resolution full north polar thermal models (Paige et al 2013;Chabot et al 2018a;Gläser & Oberst 2022). However, our thermal models also indicate the presence of regions with maximum temperatures that preclude the long-term stability of surface water ice, notably within the PSR at Kandinsky.…”

Section: Methodssupporting

confidence: 79%

“…For this study, we produced new topographic, illumination, and thermal models for Kandinsky, Tolkien, Chesterton, and Tryggvadóttir. Existing models for these four northernmost craters were previously concerned with investigating the entire north polar region and were at an insufficient resolution (250 m pixel −1 ; Paige et al 2013;Chabot et al 2018a;Gläser & Oberst 2022) for conducting detailed comparisons to the highresolution (Table 1) MDIS images of these four craters (Chabot et al 2014). We addressed this disparity in resolution by making new, higher-resolution (125 m pixel −1 ) digital elevation models (DEMs)-the highest resolution achieved for models of these craters to date.…”

Section: Methodsmentioning

confidence: 99%

“…There is already evidence that water ice is not uniformly distributed among the available cold traps at either Mercury's north (Deutsch et al 2016) or south (Chabot et al 2018b) poles given the apparent absence of strong radar backscatter in many PSRs, though potential biases in the composite radar products can complicate such investigations (Gläser & Oberst 2022). Independent of radar backscatter, surface roughness derived from MLA measurements is also suggestive of variations in ice abundance between and within individual north polar PSRs (Deutsch et al 2022).…”

Section: Radar Analysismentioning

confidence: 99%

“…The Mercury Dual Imaging System (MDIS) captured multispectral images of Mercuryʼs surface, and the Mercury Laser Altimeter (MLA) measured the northern hemisphere topography (Solomon & Anderson 2018). These measurements enabled the derivation of maps of shadowed regions, which showed a considerable overlap with the radar-bright deposits near both poles (Deutsch et al 2016;Chabot et al 2018b;Barker et al 2022;Gläser & Oberst 2022;Bertone et al 2023). Modeling of the thermal conditions using the MLA-determined topography at Mer-curyʼs north polar region revealed that water ice was stable over geologic timescales within many of the permanently shadowed regions (PSRs; Paige et al 2013;Chabot et al 2018a).…”

Section: Introductionmentioning

confidence: 99%

“…In contrast to Prokofiev, the other four large craters near Mercuryʼs north pole-Kandinsky (60 km diameter), Tolkien (50 km diameter), Chesterton (37 km diameter), and Tryggvadóttir (31 km diameter)-have received little dedicated study. Each of the craters hosts an extensive radar-bright deposit (Harmon et al 2011), and thermal models of the full north polar region predict water ice exposed at the surface within each of their PSRs (Paige et al 2013;Chabot et al 2018a;Gläser & Oberst 2022). MDIS images revealed the permanently shadowed surfaces within these four craters, but a clear conclusion regarding the surface reflectance or presence of surface water ice could not be reached owing to the challenging illumination conditions of the images (Chabot et al 2014).…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Investigating the Stability and Distribution of Surface Ice in Mercury’s Northernmost Craters

et al. 2023

View full text Add to dashboard Cite

Observations made by Earth-based radar telescopes and the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft provided compelling evidence for water ice in Mercury's polar craters. In our investigation, we constructed higher-resolution (125 m pixel−1) digital elevation models (DEMs) for four of the largest northernmost craters, Kandinsky, Tolkien, Chesterton, and Tryggvadóttir. The DEMs were leveraged to model solar illumination and the thermal environment, products that were used to identify permanently shadowed regions and simulate surface temperatures. From these models, we predicted the regions of surface stability for ice and volatile organic compounds. These predictions were then compared against the Arecibo radar, Mercury Laser Altimeter (MLA), and Mercury Dual Imaging System (MDIS) data. Our radar analysis shows that areas of high radar backscatter are correlated with areas predicted to host surface ice. Additionally, we identify radar backscatter heterogeneities within the deposits that could be associated with variations in ice purity, mantling of the ice, or ice abundances. The MDIS analysis did not reveal conclusive evidence for ice or volatiles at the surface, while MLA results support the presence of water ice at the surface in these craters. However, evidence for boundaries between the surface ice and low-reflectance volatile organic compounds, as suggested could be present by our models, was inconclusive owing to the limited MESSENGER data in these regions. BepiColombo’s upcoming orbital mission at Mercury has the opportunity to obtain new measurements of these high-latitude craters and test our predictions for the distribution of surface volatiles in these environments.

show abstract

Section: Methodssupporting

confidence: 79%

Section: Methodsmentioning

confidence: 99%

Section: Radar Analysismentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Investigating the Stability and Distribution of Surface Ice in Mercury’s Northernmost Craters

et al. 2023

View full text Add to dashboard Cite

show abstract

How Does the Thermal Environment Affect the Exosphere/Surface Interface at Mercury?

Leblanc,

Sarantos,

Domingue

et al. 2023

Planet. Sci. J.

View full text Add to dashboard Cite

The fate of Mercury’s exospheric volatiles and, in a lesser way, of the refractory particles absorbed in the first few centimeters of the surface both depend highly on the temperature profile with depth and its diurnal variation. In this paper, we review several mechanisms by which the surface temperature might control the surface/exosphere interface. The day/night cycle of the surface temperature and its orbital variation, the temperature in the permanent shadow regions, and the subsurface temperature profiles are key thermal properties that control the fate of the exospheric volatiles through the volatile ejection mechanisms, the thermal accommodation, and the subsurface diffusion. Such properties depend on the solar illumination from large to small scales but also on the regolith structure. The regolith is also space-weathered by the thermal forcing and by the thermal-mechanical processing. Its composition is changed by the thermal conditions. We conclude by discussing key characteristics that need to be investigated theoretically and/or in the laboratory: the dependency of the surface spectra with respect to temperature, the typical diffusion timescale of the volatile species, and the thermal dependency of their ejection mechanisms.

show abstract

Modeling the thermal environment of Mercury’s north pole using MLA. Implications for locations of water ice

Cited by 2 publications

References 31 publications

Investigating the Stability and Distribution of Surface Ice in Mercury’s Northernmost Craters

Investigating the Stability and Distribution of Surface Ice in Mercury’s Northernmost Craters

How Does the Thermal Environment Affect the Exosphere/Surface Interface at Mercury?

Contact Info

Product

Resources

About