Evidence of a metal-rich surface for the Asteroid (16) Psyche from interferometric observations in the thermal infrared

Matter, A.; Delbò, M.; Carry, B.; Ligori, S.

doi:10.1016/j.icarus.2013.06.004

Cited by 79 publications

(87 citation statements)

References 57 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the region between 2.8 and 3.05, there is just one large object, (16) Psyche, which is volatile-poor (Kuzmanoski & Kovačević 2002). This asteroid has an estimated diameter of about 250 km and a metallic-rich surface as inferred by diverse measurements (Ostro et al 1985;Viateau 2000;Matter et al 2013). According to our current understanding, this object should be the inner core of a differentiated object that was completely disrupted.…”

Section: Large Objectsmentioning

confidence: 95%

On the current distribution of main belt objects: Constraints for evolutionary models

Michtchenko

Lazzaro

Carvano

2016

A&A

View full text Add to dashboard Cite

Context. It is widely accepted that the current distribution of material in the main asteroidal belt (MB) is a product of the evolutionary history of the solar system during its whole lifetime of ∼4.5 billions of years and is, consequently, a major witness of the diverse stages of this evolution. Aims. The purpose of this paper is twofold: first, we study the principal aspects of the distribution of the asteroids in proper element space, mass, and, physical composition for a complete picture of the current MB. Second, we analyze if and how these current distributions can be explained by the long-lasting dynamical effects of the planets on this region of the solar system. Methods. We studied the distribution in the proper element space for the sample that consists of about 350 000 objects whose proper orbital elements are available from the database AstDyS. We studied the distribution in size and physical composition using the most recent and large available datasets. We constructed the dynamical portrait of the MB in form of the dynamical and averaged maps via the spectral analysis method. Results. The main properties of the current distributions of MB objects are identified. A comparison of the distributions of real objects with dynamical maps allows us to detect principal mechanisms of the diffusive transportation of the objects. These mechanisms are related to mean-motion resonances (MMRs) and secular resonances (SRs), overlaying with the slow dissipative Yarkovsky/Yorp drift. Conclusions. We identify the most relevant distributions of the material in the MB and show that many of the current features of the MB can be explained by the interplay of diverse dynamical mechanisms due to the planetary perturbations over 4 Gyr with nongravitational effects, without the need of 'catastrophic' events or 'ad hoc' migration mechanisms during the early stages of the solar system. In this sense, the obtained distributions can provide relevant constraints for modeling the origin and evolution of the MB.

show abstract

Section: Large Objectsmentioning

confidence: 95%

On the current distribution of main belt objects: Constraints for evolutionary models

Michtchenko

Lazzaro

Carvano

2016

A&A

View full text Add to dashboard Cite

show abstract

“…The Psyche mission was selected by the NASA Discovery program to rendezvous with asteroid 16 Psyche (Elkins-Tanton et al 2017). Radar albedo (Ostro, Campbell, & Shapiro 1985;Magri et al 2007;Shepard et al 2008Shepard et al , 2017, thermal inertia (Matter et al 2013), and density estimation (Kuzmanoski & Kovačević 2002) indicate that this asteroid has a predominantly metal-rich surface.…”

Section: Hedwigmentioning

confidence: 97%

AKARI/IRC near-infrared asteroid spectroscopic survey: AcuA-spec

Usui

Hasegawa

Ootsubo

et al. 2018

Publications of the Astronomical Society of Japan

View full text Add to dashboard Cite

Knowledge of water in the solar system is important for understanding of a wide range of evolutionary processes and the thermal history of the solar system. To explore the existence of water in the solar system, it is indispensable to investigate hydrated minerals and/or water ice on asteroids. These water-related materials show absorption features in the 3-µm band (wavelengths from 2.7 to 3.1 µm). We conducted a spectroscopic survey of asteroids in the 3-µm band using the Infrared Camera (IRC) on board the Japanese infrared satellite AKARI. In the warm mission period of AKARI, 147 pointed observations were performed for 66 asteroids in the grism mode for wavelengths from 2.5 to 5 µm. According to these observations, most C-complex asteroids have clear absorption features (> 10% with respect to the continuum) related to hydrated minerals at a peak wavelength of approximately 2.75 µm, while S-complex asteroids have no significant feature in this wavelength range. The present data are released to the public as the Asteroid Catalog using AKARI Spectroscopic Observations (AcuA-spec).

show abstract

“…Mid-infrared interferometry can provide direct measurements of the angular extension of asteroids (Delbo et al 2009;Matter et al 2011Matter et al , 2013. We used the MID-infrared Interferometric instrument (MIDI) of the Very Large Telescope Interferometer (VLTI), combining two of the 8.2 m Unitary Telescopes, UT1 and UT2, with a baseline separation of 57 m, providing a high angular resolution of λ 2B ≈ 0.02 ′′ at λ ≈ 10 µm, corresponding to about 10 km projected at the distance of Isberga at the time of observation.…”

Section: Mid-infrared Interferometrymentioning

confidence: 99%

“…The correlated flux measurements of (939) Isberga were extracted using the data reduction software package EWS (Expert WorkStation, see Jaffe 2004, for a detailed description). Using the closest calibrator observation in time, calibrated correlated fluxes of (939) Isberga were obtained by multiplying the ratio target/calibration star raw correlated flux counts by the absolutely calibrated infrared flux of the calibrator (see Matter et al 2011Matter et al , 2013, for a complete description of the data reduction and calibration procedure).…”

Section: Mid-infrared Interferometrymentioning

confidence: 99%

The small binary asteroid (939) Isberga

Carry

Matter

Scheirich

et al. 2015

Icarus

View full text Add to dashboard Cite

In understanding the composition and internal structure of asteroids, their density is perhaps the most diagnostic quantity. We aim here to characterize the surface composition, mutual orbit, size, mass, and density of the small main-belt binary asteroid (939) Isberga. For that, we conduct a suite of multi-technique observations, including optical lightcurves over many epochs, near-infrared spectroscopy, and interferometry in the thermal infrared. We develop a simple geometric model of binary systems to analyze the interferometric data in combination with the results of the lightcurve modeling. From spectroscopy, we classify Ibserga as a Sqtype asteroid, consistent with the albedo of 0.14 +0.09 −0.06 (all uncertainties are reported as 3-σ range) we determine (average albedo of S-types is 0.197 ± 0.153, see Pravec et al., 2012, Icarus 221, 365-387). Lightcurve analysis reveals that the mutual orbit has a period of 26.6304 ± 0.0001 h, is close to circular (eccentricity lower than 0.1), and has pole coordinates within 7• of (225 • ,+86• ) in Ecliptic J2000, implying a low obliquity of 1.5 +6.0 −1.5 degree. The combined analysis of lightcurves and interferometric data allows us to determine the dimension of the system and we find volume-equivalent diameters of 12.4 +2.5 −1.2 km and 3.6 +0.7 −0.3 km for Isberga and its satellite, circling each other on a 33 km wide orbit. Their density is assumed equal and found to be 2.91 +1.72 −2.01 g.cm −3 , lower than that of the associated ordinary chondrite meteorites, suggesting the presence of some macroporosity, but typical of S-types of the same size range (Carry, 2012, P&SS 73, 98-118). The present study is the first direct measurement of the size of a small main-belt binary. Although the interferometric observations of Isberga are at the edge of MIDI capabilities, the method described here is applicable to others suites of instruments (e.g., LBT, ALMA).

show abstract

Evidence of a metal-rich surface for the Asteroid (16) Psyche from interferometric observations in the thermal infrared

Abstract: We describe the first determination of thermal properties and size of the

Cited by 79 publications

References 57 publications

On the current distribution of main belt objects: Constraints for evolutionary models

On the current distribution of main belt objects: Constraints for evolutionary models

AKARI/IRC near-infrared asteroid spectroscopic survey: AcuA-spec

The small binary asteroid (939) Isberga

Contact Info

Product

Resources

About