The SSDC contribution to the improvement of knowledge by means of 3D data projections of minor bodies

The latest developments of planetary exploration missions devoted to minor bodies required new solutions to correctly visualize and analyse data acquired over irregularly shaped bodies. ASI Space Science Data Center (SSDC-ASI, formerly ASDC-ASI Science Data Center) worked on this task since early 2013, when started developing the web tool MATISSE (Multi-purpose Advanced Tool for the Instruments of the Solar System Exploration) mainly focused on the Rosetta/ESA space mission data. In order to visualize very high-resolution shape models, MATISSE uses a Python module (vtpMaker), which can also be launched as a stand-alone command-line software. MATISSE and vtpMaker are part of the SSDC contribution to the new challenges imposed by the "orbital exploration" of minor bodies: 1) MATISSE allows to search for specific observations inside datasets and then analyse them in parallel, providing high-level outputs; 2) the 3D capabilities of both tools are critical in inferring information otherwise difficult to retrieve for non-spherical targets and, as in the case for the GIADA instrument onboard Rosetta, to visualize data related to the coma. New tasks and features adding valuable capabilities to the minor bodies SSDC tools are planned for the near future thanks to new collaborations

Spin Temperatures of Ammonia and Water Molecules in Comets

The nuclear spin temperature, which is derived from the ortho-to-para abundance ratio of molecules measured in cometary comae, is a clue to the formation conditions of cometary materials, especially the physical temperature at which the molecules were formed. In this paper we present new results for the nuclear spin temperatures of ammonia in comets Hale-Bopp (C/1995 O1) and 153P/Ikeya-Zhang based on observations of NH2 at 26 and 32 K, respectively. These results are similar to previous measurements in two other comets, and the nuclear spin temperatures of ammonia in the four comets are concentrated at about 30 K. We emphasize that the nuclear spin temperatures of water measured thus far have also been about 30 K. In particular, the spin temperatures of ammonia and water are equal to each other within ±1 σ error bars in the case of comet Hale-Bopp. These nuclear spin temperatures of ammonia and water were measured under quite different conditions (heliocentric distances and gas production rates). There is no clear trend between the nuclear spin temperatures and the heliocentric distances, the gas production rates, or the orbital periods of the comets. The possibilities of the ortho-to-para conversion in the coma and in the nucleus are discussed. The present data set implies that the ortho-to-para ratios were not altered after the molecules were incorporated into the cometary nuclei. It appears that cometary ammonia and water molecules formed on cold grains at about 30 K

Ceres water regime: surface temperature, water sublimation and transient exo(atmo)sphere

Recent observations of water emission around Ceres suggest the presence of an ice layer on or beneath the surface of this asteroid. Several mechanisms have been suggested to explain these plumes, among which cometary-like sublimation seems to be plausible, since there is a correlation between the magnitude of the emission and the change in the heliocentric distance along the orbit. In this work, we applied a comet sublimation model to study the plausible scenarios that match with Herschel observations of the water flux (1026 molecules s-1). Each scenario is characterized by a well-defined set of physical and orbital parameters. Moreover, a study of the dynamic evolution of the H2O plume has been performed, showing that an optically thin transient atmospheric envelope, with a typical timescale of some tens of days, can be maintained by the H2O surface emission. Our simulations could be useful theoretical support for the Dawn NASA mission by giving a better understanding of the physical conditions for water sublimation and ice stability

Triple F - A Comet Nucleus Sample Return Mission

The Triple F (Fresh From the Fridge) mission, a Comet Nucleus Sample Return, has been proposed to ESA s Cosmic Vision program. A sample return from a comet enables us to reach the ultimate goal of cometary research. Since comets are the least processed bodies in the solar system, the proposal goes far beyond cometary science topics (like the explanation of cometary activity) and delivers invaluable information about the formation of the solar system and the interstellar molecular cloud from which it formed. The proposed mission would extract three samples of the upper 50 cm from three locations on a cometary nucleus and return them cooled to Earth for analysis in the laboratory. The simple mission concept with a touch-and-go sampling by a single spacecraft was proposed as an M-class mission in collaboration with the Russian space agency ROSCOSMOS

Comet 67P/CG: surface temperature maps from Rosetta/VIRTIS during the pre-landing phase

It was seldom possible, with observations carried out from spaceborne facilities, to derive spatially-resolved thermal maps of small bodies, and even more rarely this result was achieved in the case of close observations of comets. The Visible InfraRed Thermal Imaging Spectrometer (VIRTIS) onboard the Rosetta Orbiter Coradini (2007) is able to obtain hyperspectral images of the observed targets in 864 wavelengths simultaneously, in the overall spectral range 0.25-5.1 μm, with the major goal of inferring and mapping the surface composition and temperature of comet 67P/Churyumov-Gerasimenko. VIRTIS spectra acquired on the dayside of the comet’s nucleus show the thermal emission of the surface at wavelengths ¿ 3.5 μm, which can be ex- ploited to derive and map the surface temperature at different spatial scales and under changing lighting conditions. To do this, we rely on a Bayesian approach that was previously adopted to derive surface temperature maps of the two asteroids 2678 Steins and 21 Lutetia, encountered by Rosetta during its long cruise phase towards the comet Coradini (2011); Keihm (2012), and of the large asteroid Vesta from the entire infrared dataset acquired by the VIR instrument onboard the Dawn spacecraft Tosi (2014). In this paper we summarize the main results concerning the thermal mapping of comet 67P, obtained by VIRTIS in the first months of observation at a reso- lution between 1000 and 1 m, and at a heliocentric distance between 3.6 and 3.4 AU. Comet 67P was shown to be everywhere rich in organic materials with little to no water ice visible on the surface Capaccioni (2015). In the range of heliocentric distances from 3.59 to 2.74 AU, daytime surface temperatures were overall comprised in the range between 180 and 220 K Tosi (2015), which is incompatible with large exposures of water ice and is consistent with a low-albedo, organics-rich surface. Maximum temperature values as high as 230 K were recorded in very few places Tosi (2015). In the above period, the highest values of surface temperature were obtained with observations carried out at small phase angles, implying that the observed surface has a large predominance of small incidence angles, and local solar times centered around the max- imum daily insolation. In all cases, direct correlation with topographic features was observed, i.e. largest temperature values were generally associated with the smallest values of illumination angles, while no evidence was found of thermal anomalies, i.e. places of the surface that are intrinsically warmer or cooler than surrounding terrains observed at the same local solar time and under similar solar illumination

BC-SIM-TR-003 - STC NECP Report

The present document has been issued with the aim of describing the NECP (Near Earth Commissioning Phase) Tests of STC the Stereo Camera part of SIMBIO-SYS instrument, payload of the BepiColombo mission

Italian Report to the 43rd COSPAR Scientific Assembly

This document summarizes the last two years of space science activity in Italy and is the Italian Report to the 43rd COSPAR General Assembly. It is edited by INAF, the formal Italian national body that by the law supports the COSPAR activities, with the collaboration of ASI and the other stakeholders playing a major role in the Italian scientific space programs (INFN, CNR, INGV, etc.). In view of the appreciation received for the former editions, this year the Report has been formulated in a similar condensed form to give the relevant information in a snapshot, though providing a fully updated overview of the Italian research programs carried out from space. We apologize for any omission or misunderstanding. The Report is organized with the description of the scientific goals, technical requirements and actual realization of the space missions, enumerated following the COSPAR Scientific Commissions scheme: https://cosparhq.cnes.fr/scientific-structure/scientific-commissions/ Italy is today deeply involved in space science with a multifaceted activity. A remarkable sequence of scientific results over the past years and a considerable number of projects driven by Italian scientists, engineers and technologists position Italy as a frontrunner in space astrophysicsand space physics

IDIS Small Bodies and Dust Node: Technical innovation and science

This work was supported by the EUROPLANET RI FP7 grant agreement 228319It is not trivial, nowadays, to be fully aware of the impressive amount of astrophysical resources that are at hand. Virtual Observatories (VOs) were therefore created to provide a simple access to what astronomers look for. In this paper we focus on the original data access services developed specifically, in a VO perspective, for the "Small Bodies and Dust Node" (SBDN) in the framework of the Integrated and Distributed Information System (IDIS) initiative of the Europlanet Research Infrastructure project. We describe the scientific goals, along with the innovative technical aspects, of the tools that SBDN presently provides to the scientific community, namely the Comet Emission Lines service, and the Cosmic Dust Catalog service. In the former, an algorithm for the detection of unidentified emission lines has been implemented