Spheroidal and ellipsoidal harmonic expansions of the gravitational potential of small Solar System bodies. Case study: Comet 67P/Churyumov-Gerasimenko

The XXIX IAU General Assembly took place during the golden year of the exploration of small solar system bodies. With the Rosetta ESA mission around comet 67P, NASA Dawn and New Horizons missions nearby dwarf planets Ceres and Pluto, respectively, and the NASA/Cassini mission in Saturn neighborhood, year 2015 marked an important step towards further understanding of small solar system bodies. On August 11-13, Focus meeting 9 "Highlights in the exploration of small worlds" gathered scientists of all over the world to present and discuss the spectacular results obtained from these missions, as well as recent achievements obtained from past missions, comprehensive spectroscopic surveys from space (e.g., Herschel, NEOWISE, Gaia), ground-based observations, and geochemical analyses. This meeting was also the opportunity to discuss the state of our understanding of the nature of the various populations of small bodies in the Solar System, including icy satellites, in a cosmo-chemistry perspective.

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Spectropolarimetric device for overatmospheric investigations of Solar system bodies

Kosmìčna nauka ì tehnologìâ ◽

10.15407/knit2008.02.056 ◽

2008 ◽

Vol 14 (2) ◽

pp. 56-67

Author(s):

Ya.S. Yatskiv ◽

◽

A.P. Vidmachenko ◽

O.V. Morozhenko ◽

M.G. Sosonkin ◽

...

Keyword(s):

Solar System ◽

Solar System Bodies

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Organic matter and water from asteroid Itokawa

Scientific Reports ◽

10.1038/s41598-021-84517-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Q. H. S. Chan ◽

A. Stephant ◽

I. A. Franchi ◽

X. Zhao ◽

R. Brunetto ◽

...

Keyword(s):

Organic Matter ◽

Solar System ◽

Parent Body ◽

Asteroid Belt ◽

True Nature ◽

Water Ice ◽

Nanocrystalline Graphite ◽

Terrestrial Water ◽

Solar System Bodies ◽

Small Dust

AbstractUnderstanding the true nature of extra-terrestrial water and organic matter that were present at the birth of our solar system, and their subsequent evolution, necessitates the study of pristine astromaterials. In this study, we have studied both the water and organic contents from a dust particle recovered from the surface of near-Earth asteroid 25143 Itokawa by the Hayabusa mission, which was the first mission that brought pristine asteroidal materials to Earth’s astromaterial collection. The organic matter is presented as both nanocrystalline graphite and disordered polyaromatic carbon with high D/H and 15N/14N ratios (δD = + 4868 ± 2288‰; δ15N = + 344 ± 20‰) signifying an explicit extra-terrestrial origin. The contrasting organic feature (graphitic and disordered) substantiates the rubble-pile asteroid model of Itokawa, and offers support for material mixing in the asteroid belt that occurred in scales from small dust infall to catastrophic impacts of large asteroidal parent bodies. Our analysis of Itokawa water indicates that the asteroid has incorporated D-poor water ice at the abundance on par with inner solar system bodies. The asteroid was metamorphosed and dehydrated on the formerly large asteroid, and was subsequently evolved via late-stage hydration, modified by D-enriched exogenous organics and water derived from a carbonaceous parent body.

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Microstructural features in carbonates from Antarctic micrometeorites: Effective tools for analyzing the evolution of small Solar System bodies

Microscopy and Microanalysis ◽

10.1017/s1431927621009740 ◽

2021 ◽

Vol 27 (S1) ◽

pp. 2778-2781

Author(s):

Elena Dobrica ◽

Kenta Ohtaki ◽

Cecile Engrand

Keyword(s):

Solar System ◽

Solar System Bodies

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CAN GENERAL RELATIVISTIC DESCRIPTION OF GRAVITATION BE CONSIDERED COMPLETE?

Modern Physics Letters A ◽

10.1142/s0217732398001455 ◽

1998 ◽

Vol 13 (17) ◽

pp. 1393-1400 ◽

Cited By ~ 16

Author(s):

D. V. AHLUWALIA

Keyword(s):

Solar System ◽

Gravitational Potential ◽

Invariance Properties ◽

Planetary Orbits ◽

Galactic Cluster ◽

General Relativistic ◽

Relativistic Description ◽

Flavor Oscillation ◽

Weak Fields ◽

Great Attractor

The local galactic cluster, the Great attractor, embeds us in a dimensionless gravitational potential of about -3×10-5. In the solar system, this potential is constant to about 1 part in 1011. Consequently, planetary orbits, which are determined by the gradient in the gravitational potential, remain unaffected. However, this is not so for the recently introduced flavor-oscillation clocks where the new redshift-inducing phases depend on the gravitational potential itself. On these grounds, and by studying the invariance properties of the gravitational phenomenon in the weak fields, we argue that there exists an element of incompleteness in the general relativistic description of gravitation. An incompleteness-establishing inequality is derived and an experiment is outlined to test the thesis presented.

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The Grand Tack model: a critical review

Proceedings of the International Astronomical Union ◽

10.1017/s1743921314008254 ◽

2014 ◽

Vol 9 (S310) ◽

pp. 194-203 ◽

Cited By ~ 12

Author(s):

Sean N. Raymond ◽

Alessandro Morbidelli

Keyword(s):

Solar System ◽

Building Blocks ◽

Protoplanetary Disk ◽

Giant Planets ◽

Asteroid Belt ◽

Terrestrial Planets ◽

Saturn’S Satellites ◽

Internal Inconsistency ◽

Solar System Bodies ◽

Gas Accretion

AbstractThe “Grand Tack” model proposes that the inner Solar System was sculpted by the giant planets' orbital migration in the gaseous protoplanetary disk. Jupiter first migrated inward then Jupiter and Saturn migrated back outward together. If Jupiter's turnaround or “tack” point was at ~ 1.5 AU the inner disk of terrestrial building blocks would have been truncated at ~ 1 AU, naturally producing the terrestrial planets' masses and spacing. During the gas giants' migration the asteroid belt is severely depleted but repopulated by distinct planetesimal reservoirs that can be associated with the present-day S and C types. The giant planets' orbits are consistent with the later evolution of the outer Solar System.Here we confront common criticisms of the Grand Tack model. We show that some uncertainties remain regarding the Tack mechanism itself; the most critical unknown is the timing and rate of gas accretion onto Saturn and Jupiter. Current isotopic and compositional measurements of Solar System bodies – including the D/H ratios of Saturn's satellites – do not refute the model. We discuss how alternate models for the formation of the terrestrial planets each suffer from an internal inconsistency and/or place a strong and very specific requirement on the properties of the protoplanetary disk.We conclude that the Grand Tack model remains viable and consistent with our current understanding of planet formation. Nonetheless, we encourage additional tests of the Grand Tack as well as the construction of alternate models.

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