Physical Properties of Near-Earth Asteroids

In orbits that cross the Earth's orbit, there are many small bodies - near-Earth asteroids (NEAs), which constitute a potential threat of collision with the Earth. The study of their physical and dynamical parameters is required to assess the risk of such an impact for our civilization. Currently, the process of NEAs discovery is much faster than getting data on physical parameters of these bodies. Acquisition of such characteristics as sizes, shapes, rotation parameters, surface composition, densities will permit to evaluate the degree of risk and the possibility of preventing potentially catastrophic impacts with the Earth.

Photometry of NEAs

Since 2006 we carry out photometric observations of near-Earth asteroids in cooperation with the International Scientific Optical Network (ISON). Our observations are mainly aimed at getting lightcurves to determine the rotational periods, sizes and shapes of NEAs. We focus our research on the study of binary asteroids, and detection and investigation of the YORP effect. Particular interest is devoted to Potentially Hazardous Asteroids (PHAs) and the newly discovered NEAs accessible for photometry with the ISON telescopes. We also carry out photometric observations of NEAs in support of radar observations.

Details on the methods of observations and results of NEAs photometry can be found in:

Krugly Yu. N., I. N. Belskaya, V. G. Shevchenko et al. 2002. CCD Photometry of Near-Earth asteroids in 1996-1999. Icarus 158, p.294-304.

Krugly Yu. N., N. M. Gaftonyuk, I. N. Belskaya et al. 2007. Kharkiv study of near-Earth asteroids. Proceedings of IAU Symposium 236. Near Earth Objects, our Celestial Neighbors: Opportunity and Risk. Edited by G. B. Valsecchi and D. Vokrouhlicky. – Cambridge: Cambridge University Press, p.385-390.

The list of current targets is available in the section Observations.

Polarimetry of NEAs

Polarimetry is a very useful alternative technique for the albedo determination. The albedo can be derived directly from observations based on relations between the albedo and the degree of linear polarization. Moreover, even a single polarization measurement at large phase angles (accessible only for NEAs) provide an immediate clue to whether a given asteroid is a low-albedo, moderate albedo or high-albedo object.

Example of using polarimetric technique to estimate albedo and size of potentially hazardous asteroid (23187) 2000 PN9 can be found in

Belskaya I.N., Fornasier S., Krugly Y.N. (2009) Polarimetry and BVRI photometry of the potentially hazardous near-Earth Asteroid (23187) 2000 PN9. Icarus 201, p.167–171. pdf

The list of current targets is available in the section Observations.