Related papers: Compositional characterisation of the Themis famil…
Themis family is one of the largest and oldest asteroid populations in the main-belt. Water-ice may widely exist on the parent body (24) Themis. In this work, we employ the Advanced Thermophysical Model as well as mid-infrared measurements…
Themis is an old and statistically robust asteroid family populating the outer main belt, and resulting from a catastrophic collision that took place 2.5$\pm$1.0 Gyr ago. Within the old Themis family a young sub-family, Beagle, formed less…
We present visible spectroscopic and albedo data of the 2.3 Gyr old Themis family and the <10 Myr old Beagle sub-family. The slope and albedo variations between these two families indicate C-complex asteroids become redder and darker in…
Large main-belt asteroids (diameter $D \gtrsim 120\ \mathrm{km}$) exhibit a surface composition gradient as a function of heliocentric distance, ranging from anhydrous bodies to those rich in hydrated and, possibly, ammoniated materials.…
Low-albedo, hydrated objects dominate the list of the largest asteroids. These objects have varied spectral shapes in the 3-$\mu$m region, where diagnostic absorptions due to volatile species are found. Dawn's visit to Ceres has extended…
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 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…
This study presents the first optical spectropolarimetric study of large C-complex asteroids. A total of 64 C-complex asteroids of different subclasses are analyzed using archival polarimetric and reflectance data to refine the link between…
We report the results of a search for a dust trail aligned with the orbit plane of the large main-belt asteroid (24) Themis, which has been reported to have water ice frost on its surface. Observations were obtained with the GMOS instrument…
By means of a varied-shape thermophysical model (VS-TPM) of Hanus et al. (2015) that takes into account asteroid shape and pole uncertainties, we analyze the thermal IR data acquired by the NASA's WISE satellite of about 300 asteroids with…
A hypothesis based on observational and theoretical results on the origin of C-type asteroids and carbonaceous chondrites is proposed. Asteroids of C-type and close BGF-types could form from hydrated silicate-organic matter accumulated in…
Observations of C-type NEAs and lab investigations of carbonaceous chondritic (CC) meteorites provide strong evidence for a high porosity of C-type asteroids. Boulder microporosity values derived from in-situ measurements at the surface of…
Photometric lightcurves were also obtained for 14 of them during the Spitzer observations to provide the context of the observations and reliable estimates of their absolute magnitudes. The extracted mid-IR spectra were analyzed using a…
Most C-complex asteroids have albedo values less than 0.1, but there are some high-albedo (bright) C-complex asteroids with albedo values exceeding 0.1. To reveal the nature and origin of bright C-complex asteroids, we conducted…
Recent dynamical analyses suggest that some Jupiter family comets (JFCs) may originate in the main asteroid belt instead of the outer solar system. This possibility is particularly interesting given evidence that icy main-belt objects are…
Aims: Our aim is to obtain more information about the physical nature of B-type asteroids and extend on the previous work by studying their physical properties derived from fitting an asteroid thermal model to their NASA's Wide-field…
Although petrologic, chemical and isotopic studies of ordinary chondrites and meteorites in general have largely helped establish a chronology of the earliest events of planetesimal formation and their evolution, there are several questions…
Context. CM-like asteroids (Ch and Cgh classes) are a major population within the broader C-complex, encompassing about 10% of the mass of the main asteroid belt. Their internal structure has been predicted to be homogeneous, based on their…
Asteroid (16) Psyche, that for long was the largest M-type with no detection of hydration features in its spectrum, was recently discovered to have a weak 3 micron band and thus it eventually was added to the group of hydrated asteroids.…
A considerable amount of information regarding the processes that occurred during the accretion of the early planetesimals is still present among the small bodies of our solar system. A review of our current knowledge of the density of…