저작근 근전도에 관한 정상교합자와 ii급 부정교합자의 비교 연구

1. Introduction 2. Radial velocities 3. Astrometry 4. Timing 5. Microlensing 6. Transits 7. Imaging 8. Host stars 9. Brown dwarfs and free-floating planets 10. Formation and evolution 11. Interiors and atmospheres 12. The Solar System Appendixes References Index.

/pdf/the-exoplanet-handbook-3g3nzlvc20.pdf

The Exoplanet Handbook

Jets of water ice from surface fractures near the south pole of Saturn's icy moon Enceladus produce a plume of gas and particles. The source of the jets may be a liquid water region under the ice shell-as suggested most recently by the discovery of salts in E-ring particles derived from the plume-or warm ice that is heated, causing dissociation of clathrate hydrates. Here we report that ammonia is present in the plume, along with various organic compounds, deuterium and, very probably, Ar-40. The presence of ammonia provides strong evidence for the existence of at least some liquid water, given that temperatures in excess of 180 K have been measured near the fractures from which the jets emanate. We conclude, from the overall composition of the material, that the plume derives from both a liquid reservoir (or from ice that in recent geological time has been in contact with such a reservoir) as well as from degassing, volatile-charged ice. As part of a general comprehensive review of the midsize saturnian satellites at the conclusion of the prime Cassini mission, PI McKinnon and co-I Barr contributed to three review chapters.

Liquid water on Enceladus from observations of ammonia and 40Ar in the plume

JUpiter ICy moons Explorer (JUICE): An ESA mission to orbit Ganymede and to characterise the Jupiter system

With the exception of in situ atmospheric probes, the most useful way to study the atmospheres of other planets is to observe their electromagnetic spectra through remote observations, either from ground-based telescopes or from spacecraft. Atmospheric properties most consistent with these observed spectra are then derived with retrieval models. All retrieval models attempt to extract the maximum amount of atmospheric information from finite sets of data, but while the problem to be solved is fundamentally the same for any planetary atmosphere, until now all such models have been assembled ad hoc to address data from individual missions.

In this paper, we describe a new general-purpose retrieval model, Non-linear Optimal Estimator for MultivariatE Spectral analySIS (NEMESIS), which was originally developed to interpret observations of Saturn and Titan from the composite infrared spectrometer on board the NASA Cassini spacecraft. NEMESIS has been constructed to be generally applicable to any planetary atmosphere and can be applied from the visible/near-infrared right out to microwave wavelengths, modelling both reflected sunlight and thermal emission in either scattering or non-scattering conditions. NEMESIS has now been successfully applied to the analysis of data from many planetary missions and also ground-based observations.

The NEMESIS planetary atmosphere radiative transfer and retrieval tool

Surface Composition of Saturn's Icy Moons

A New Estimate of the Power Emitted by Enceladus' Tiger Stripes

Ring and Magnetosphere Interactions with Satellite Surfaces

A review of thermophysical surface models in preparation for E-THEMIS observations of Europa

A near-surface thermal model for Arrokoth is developed based on the recently released 105 facet model of the body. This thermal solution takes into account Arrokoth’s surface reradiation back onto itself. The solution method exploits Arrokoth’s periodic orbital character to develop a thermal response using a time-asymptotic solution method, which involves a Fourier transform solution of the heat equation, an approach recently used by others. We display detailed thermal solutions assuming that Arrokoth’s near-surface material’s thermal inertia = 2.5 W/m−2 K−1 s1/2. We predict that at New Horizons’ encounter with Arrokoth, its encounter hemisphere surface temperatures were ∼57–59 K in its polar regions, 30–40 K in its equatorial zones, and 11–13 K for its winter hemisphere. Arrokoth’s orbitally averaged temperatures are around 30–35 K in its polar regions and closer to 40 K near its equatorial zones. Thermal reradiation from the surrounding surface amounts to less than 5% of the total energy budget, while the total energy ensconced into and exhumed out of Arrokoth’s interior via thermal conduction over one orbit is about 0.5% of the total energy budget. As a generalized application of this thermal modeling together with other Kuiper Belt object origins considerations, we favor the interpretation that New Horizons’ REX instrument’s 29 ± 5 K brightness temperature measurement is consistent with Arrokoth’s near-surface material being made of sub-to-few-millimeter-size tholin-coated amorphous H2O ice grains with 1 W/m−2 K−1 s1/2 << 10–20 W/m−2 K−1 s1/2 and which are characterized by an X-band emissivity in the range 0.9 and 1.

Carly Howett

Papers

Surface Composition of Saturn's Icy Moons

A New Estimate of the Power Emitted by Enceladus' Tiger Stripes

Ring and Magnetosphere Interactions with Satellite Surfaces

A review of thermophysical surface models in preparation for E-THEMIS observations of Europa

A Near-surface Temperature Model of Arrokoth