Related papers: A Near-Infrared Search for Silicates in Jovian Tro…
We have used the XSHOOTER echelle spectrograph on the European Southern Obseratory (ESO) Very Large Telescope (VLT) to obtain UVB-VIS-NIR (ultraviolet-blue (UVB), visible (VIS) and near-infrared (NIR)) reflectance spectra of two members of…
In this work, we analyze Jovian Trojans in the space of suitable resonant elements and we identify clusters of possible collisional origin by two independent methods: the hierarchical clustering and a so-called "randombox". Compared to our…
The origin of the Jupiter Trojan asteroids has long been a mystery. Dynamically, the population, which is considerably smaller than the main asteroid belt, librates around Jupiter's stable L4 and L5 Lagrange points, 60 deg ahead and behind…
We investigated the population of asteroids in comet-like orbits using available asteroid size and albedo catalogs of data taken with the Infrared Astronomical Satellite, AKARI, and the Wide-field Infrared Survey Explorer on the basis of…
We present optical spectra of (24) Themis and (65) Cybele, two large main-belt asteroids on which exposed water ice has recently been reported. No emission lines, expected from resonance fluorescence in gas sublimated from the ice, were…
Jupiter family comet 17P/Holmes underwent a remarkable outburst on UT 2007 Oct. 24, in which the integrated brightness abruptly increased by about a factor of a million.We obtained near infrared (0.8 - 4.2 micron) spectra of 17P/Holmes on…
Enstatite chondrites and aubrites are meteorites that show the closest similarities to the Earth in many isotope systems that undergo mass-independent and mass-dependent isotope fractionations. Due to the analytical challenges to obtain…
The recent Spitzer detections of the 9.7 micron Si--O silicate emission in type 1 AGNs provide support for the AGN unification scheme. The properties of the silicate dust are of key importance to understanding the physical, chemical and…
We have investigated the infrared spectra of all 46 Herbig Ae/Be stars for which spectroscopic data is available in the ISO data archive. Our quantitative analysis of these spectra focusses on the emission bands linked to polycyclic…
Images and low-resolution spectra of the near-Earth Jupiter family comet (JFC) 249P/LINEAR in the visible range obtained with the instrument OSIRIS in the 10.4m Gran Telescopio Canarias on January 3, 4, 6 and February 6, 2016 are presented,…
The unified model of active galactic nuclei (AGN) predicts silicate emission features at 10 and 18 microns in type 1 AGN, and such features have now been observed in objects ranging from distant QSOs to nearby LINERs. More surprising,…
Irregular satellites of Jupiter with their highly eccentric, inclined and distant orbits suggest that their capture took place just before the giant planet migration. We aim to improve our understanding of the surface composition of…
Context. Andesitic meteorites are among the oldest achondrites known to date. They record volcanic events and crust formation episodes in primordial planetesimals that took place about 4.565 Myr ago. However, no analogue for these…
We describe the discovery of a satellite of the Trojan asteroid (3548) Eurybates in images obtained with the Hubble Space Telescope. The satellite was detected on three separate epochs, two in September 2018 and one in January 2020. The…
We observed asteroid (596) Scheila and its ejecta cloud using the Swift UV-optical telescope. We obtained photometry of the nucleus and the ejecta, and for the first time measured the asteroid's reflection spectrum between 290 - 500 nm. Our…
Anhydrous pyroxene-rich interplanetary dust particles (IDPs) have been proposed as surface analogs for about two-thirds of all C-complex asteroids. However, this suggestion appears to be inconsistent with the presence of hydrated silicates…
We have used the InfraRed Array Camera (IRAC) onboard the Spitzer Space telescope to search for low mass companions of the nearby debris disk star epsilon Eridani. The star was observed in two epochs 39 days apart, with different focal…
We present 8--13 micron low resolution spectra (R~100) of 8 low-mass protostellar objects ("proplyds") in the Orion Nebula using the Long Wavelength Spectrometer (LWS) at the W. M. Keck Observatory. All but one of the sources in our sample…
Asteroids near the Sun can attain equilibrium temperatures sufficient to induce surface modification from thermal fracture, desiccation and decomposition of hydrated silicates. We present optical observations of nine asteroids with…
Pyroxene crystals are common in meteorites but few compositions have been recognized in astronomical environments. We present quantitative room-temperature spectra of 17 Mg-- Fe-- and Ca--bearing ortho- and clinopyroxenes, and a…