相关论文: The Chemical Composition of Mercury
Mercury, the innermost planet, formed under highly reduced conditions, based mainly on surface Fe, S, and Si abundances determined from MESSENGER mission data. The minor element Cr may serve as an independent oxybarometer, but only very…
The MESSENGER mission sought to discover what physical processes determined Mercury's high metal to silicate ratio. Instead, the mission has discovered multiple anomalous characteristics about our innermost planet. The lack of FeO and the…
The origin of Mercury still remains poorly understood compared to the other rocky planets of the Solar System. One of the most relevant constraints that any formation model has to fulfill refers to its internal structure, with a predominant…
The bulk chemical compositions of planets are uncertain, even for major elements such as Mg and Si. This is due to the fact that the samples available for study all originate from relatively shallow depths. Comparison of the stable isotope…
The Earth, Venus, Mars, and some extrasolar terrestrial planets have a mass and radius that is consistent with a mass fraction of about 30% metallic core and 70% silicate mantle. At the inner frontier of the solar system, Mercury has a…
Mercury's crust has a complex structure resulting from a billion years of volcanism. The surface variations in chemical composition have been identified from orbit by the spacecraft MESSENGER. Combining these measurements with laboratory…
High resolution images of Mercury's surface, from the MESSENGER spacecraft, reveal many bright deposits associated with irregular, shallow, rimless depressions whose origins were attributed to volatile-related activity, but absent…
Mercury's high uncompressed mass density suggests that the planet is largely composed of iron, either bound within metal (mainly Fe-Ni), or iron sulfide. Recent results from the MESSENGER mission to Mercury imply a low temperature history…
Major element fractionation among chondrites has been discussed for decades as ratios relative to Si or Mg. Recently, by expressing ratios relative to Fe, I discovered a new relationship admitting the possibility that ordinary chondrite…
The origin of Mercury's anomalous core and low FeO surface mineralogy are outstanding questions in planetary science. Mercury's composition may result from cosmochemical controls on the precursor solids that accreted to form Mercury. High…
The pathway to forming the iron-rich planet Mercury remains mysterious. Mercury's core makes up 70% of the planetary mass, which implies a significant enrichment of iron relative to silicates, while its mantle is strongly depleted in…
The bulk density of a planet, as measured by mass and radius, is a result of planet structure and composition. Relative proportions of iron core, rocky mantle, and gaseous envelopes are degenerate for a given density. This degeneracy is…
Recent observations of rocky super-Earths have revealed an apparent wider distribution of Fe/Mg ratios, or core to mantle ratios, than the planets in our Solar System. This study aims to understand how much of the chemical diversity in the…
Extrasolar planet host stars have been found to be enriched in key planet-building elements. These enrichments have the potential to drastically alter the composition of material available for terrestrial planet formation. Here we report on…
Comparing compositional models of the terrestrial planets provides insights into physicochemical processes that produced planet-scale similarities and differences. The widely accepted compositional model for Mars assumes Mn and more…
Much of a planet's composition could be determined right at the onset of formation. Laboratory experiments can constrain these early steps. This includes static tensile strength measurements or collisions carried out under Earth's gravity…
The X-Ray Spectrometer (XRS) on the MESSENGER spacecraft provided measurements of major-element ratios across Mercury's surface. We present global maps of Mg/Si, Al/Si, S/Si, Ca/Si, and Fe/Si derived from XRS data collected throughout…
We describe the current state of knowledge about Mercury's interior structure. We review the available observational constraints, including mass, size, density, gravity field, spin state, composition, and tidal response. These data enable…
In spite of substantial advancements in simulating planet formation, the planet Mercury's diminutive mass, isolated orbit, and the absence of planets with shorter orbital periods in the solar system continue to befuddle numerical accretion…
Because of their common origin, it was assumed that the composition of planet building blocks should, to a first order, correlate with stellar atmospheric composition, especially for refractory elements. In fact, information on the relative…