25 years of asteroid investigations by Kharkiv asteroid group

In the middle of the 1970s physical investigations of asteroids became quite active in the USA and partly in Europe (Italy, Austria, Sweden). It was evident that asteroids are the bodies of great interest first of all from the point of view of cosmogonic problems of the Solar System. That was the principal reason for the beginning of asteroid studies at our Institute (Astronomical Observatory, at that time). The most important results of asteroid study obtained by our group during the last 25 years are presented

Kharkiv database of asteroid absolute magnitudes : Comparative analysis with other datasets

We present a database of the absolute magnitudes of asteroids named the Kharkiv Asteroid Absolute Magnitude Database (KhAAMD). The database includes a homogeneous set of the absolute magnitudes for about 400 asteroids in the new HG(1)G(2) magnitude system. We performed a comparative analysis of the asteroid absolute magnitudes between the Kharkiv database and other main magnitude databases (MPC, Pan-STARRS, ATLAS, PTF, and Gaia). We show that the Pan-STARRS absolute magnitude dataset has no systematic deviations and is the most suitable for the determination of diameters and albedos of asteroids. For the MPC dataset, there is a linear trend of overestimating the absolute magnitudes of bright objects and underestimating the magnitudes of faint asteroids. The ATLAS dataset has both a systematic overestimation of asteroid magnitudes and a linear trend. We propose equations that can be used to correct for systematic errors in the MPC and the ATLAS magnitude datasets. There are possible systematic deviations of about 0.1 mag for the Gaia and PTF databases but there are insufficient data overlapping with our data for a definitive analysis.Peer reviewe

Physical Properties of Near-Earth Objects

The population of near-Earth objects (NEOs) contains asteroids, comets, and the precursor bodies for meteorites. The challenge for our unterstanding of NEOs is to reveal the proportions and relationships between these categories of solar-system small bodies and their source(s) of resupply. Even accounting for strong bias factors in the discovery and characterization of higher-albedo objects. NEOs having S-type spectra are proportionally more abundant than within the main asteroid belt as a whole. This, an inner asteroid belt origin (where S-type objects dominate) is implied for most NEOs. The identification of a cometary contribution within the NEO population remains one of a case-by-case examination of unusual objects, and the sum of evidence suggests that comets contribute at most only a few percent of the total. With decreasing size and younger surfaces (due to presumably shorter collisional lifetimes for smaller objects), NEOs show a transition in spectral properties toward resembling the most common meteorites, the ordinary chondrites. Ordinary chondritelike objects are no longer rare among the NEOs, and at least qualitatively it is becoming understandable why these objects comprise a high proportion of meteorite falls. Comparisons that can be performed between asteroidal NEOs and their main-belt counterparts suggest that the physical properties (e.g. rotation states, configurations, spectral colors, surface scattering) of NEOs may be represantative of main-belt asteroids (MBAs) at similar (but presently unobservable) sizes

A View to the Future: Ultraviolet Studies of the Solar System

We discuss the status of ultraviolet knowledge of Solar System objects. We begin with a short historical survey, followed by a review of knowledge gathered so far and of existing observational assets. The survey indicates that UV observations, along with data collected in other spectral bands, are necessary and in some cases essential to understand the nature of our neighbors in the Solar System. By extension, similar observations are needed to explore the nature of extrasolar planets, to support or reject astro-biology arguments, and to compose and test scenarios for the formation and evolution of planetary systems. We propose a set of observations, describing first the necessary instrumental capabilitites to collect these and outlining what would be the expected scientific return. We identify two immediate programmatic requirements: the establishment of a mineralogic database in the ultraviolet for the characterization of planetary, ring, satellite, and minor planet surfaces, and the development and deployment of small orbital solar radiation monitors. The first would extend the methods of characterizing surfaces of atmosphere-less bodies by adding the UV segment. The latter are needed to establish a baseline against which contemporaneous UV observations of Solar System objects must be compared. We identify two types of UV missions, one appropriate for a two-meter-class telescope using almost off-the-shelf technology that could be launched in the next few years, and another for a much larger (5--20 meter class) instrument that would provide the logical follow-up after a decade of utilizing the smaller facility