The Laboratory actively collaborates with a number of international organizations: IAU Commissions 4, 7, 8, 15, 16, 19, 20, JPL (Jet Propulsion Laboratory, USA), IMCCE (Institut de Mecanique Celeste et de Calcul des Ephemerides), the Celestial Mechanics sub-faculty of St.-Petersburg State University and takes part in the projects of IVS (International VLBI Service) and of ISLR (International Satellite Laser Ranging Service).

1. Developing the astronomical part of the unified Windows/Linux version of the program package ERA and supporting the DOS version available via anonymous FTP.
   The program package ERA includes:
   • Translator from the problem-oriented language SLON in which any tasks of ephemeris and dynamical astronomy may be described.
   • Integrated Development Environment (IDE) for performing the SLON programs. The IDE includes en editor for editing the SLON programs, en editor of the ERA-tables which are the structural units of the ERA database, and the online Help service.

2. Supporting and supplementing the database of optical and radiometrical observations of the major planets, their satellites, and spacecraft (currently, the database includes about 500000 observations of 1913-2008). Supporting the ERA-system database of observations and orbital elements of asteroids and comets, updating the LLR database (1970-2008) for measurements of six stations including high-precise data of Apache Observatory ("APOLLO").
   The following updated data are available:
   The Russian ranging observations of planets (1962-1995).
   Normal places of ranging to Mars Global Surveyor - MGS (1998-2006) and Odyssey (2002-2007) spacecraft , representing observations in a compressed form.

3. Developing the high-precision planet ephemerides EPM2004 constructed over the 1880-2050 year interval by the simultaneous numerical integration of the equations of motion of planets, the Moon, the Sun, 301 biggest asteroids and the lunar physical libration, with the account of perturbations due to the solar oblateness and the massive ring of small asteroids. The version of the EPM2004 theory has been adopted as the ephemeris basis of Russian Astronomical Yearbook since 2006 and is available to outside users via FTP.
   
   Improving the model and the parameters of the numerical theory of orbital and rotational motion of the Moon accounts for the effects of elasticity of the lunar body, tidal dissipation in the Moon, and friction coupling between the lunar mantle and its fluid core for processing the current LLR observations.
   The analysis of 16834 LLR data 1970-2008 was carried out applying different numerical theories DE403, DE405, DE421 and theory EPM-ERA developed in IAA RAS. The 65 parameters of lunar dynamics, coordinates of stations and lunar reflectors have been determined from LLR data.
   
   The renovation of the planet part of the EPM2008 ephemerides includes the new values of masses of planets and other bodies of the Solar System determined by different authors from spacecraft or satellite data and other improved constants, the updated dynamic model with the 21 largest trans-Neptunian objects added in a simultaneous numerical integration, as well as the updated database 1913-2008 included recent spacecraft (Odyssey, MRO, VEX, Cassini) measurements and CCD data of the outer planets and their satellites along with previous observations since 1913. Some tests have been made for estimating influence of the rest of TNO on the motion of planets. Their perturbations have been modeled by the perturbation from a circular ring having a radius 43 AU and different masses.
   More than 260 parameters have been determined while improving the planetary part of EPM2008 to observations. The data residuals don't exceed their a priori accuracies. EPM2008 have been oriented to ICRF with the accuracy better than fractions of 1 mas by including into the total solution the 118 ICRF-base VLBI measurements of different spacecraft near the planets. The comparison of our recent EPM2008 ephemeris with the standard DE405 and the latest DE421 ephemerides has been made.

4. The ephemerides of the Uranus's satellites (Ariel, Umbriel, Titania, Oberon, Miranda), the Galilean satellites of Jupiter and 3 — 8 Saturn's satellites (jointly with the Laboratory of Astronomical Yearbooks), as well as the 9-th satellite of Saturn (Phoebe), and the Neptune's satellite Triton have been constructed by numerical integration of the equations of motion for satellites systems of the outer planets. The orbital elements have been improved and other parameters of satellite ephemerides have been determined using the analysis of modern photographic and CCD satellite observations (about 30000 for 1982-2007). In particular, the eccentricity of the Triton's orbit was, for the first time, successfully derived (e=0.0028±0.003). The coefficient of the second zonal harmonics of Neptune was estimated to be 0.00294±0.00042.

5. The numerical theory of the Earth rotation was constructed and fitted to the VLBI data for the years 1984-2007. The dynamical theory includes a two-layer model of the Earth's fluid core. The values of a number of geophysical parameters (the Love number k₂, the parameters of the fluid core, the tidal phase delays of the Earth as a whole and in the fluid core, the coefficient of friction at the mantle - core boundary and some others) were improved. An attempt to estimate the dynamic Love number k₂^d, that describes an effect of a differential rotation of the fluid core relative to the mantle on the Earth's rotation, has been made from Lageos 1,2 data. About two millions of laser ranging 1988 — 2003 have been processed. The 26 independent estimates k₂^d on annual intervals have been obtained. The average weighted value k₂^d = 0.0613 ± 0.0013 that is the first experimental one has been deduced.
   The corrections to the adopted value of the J₂ geopotential coefficient and amplitudes of annual and semi-annual oscillations have been derived from the same analysis. The obtained positive trend of J₂ means that the adopted value of secular decrease of J₂ attributing usually the post-glacial relaxation should be reduced significantly.

6. The numerical theory of the Mars rotation has been constructed, the parameters of which have been determined from processing radiometric observations of Viking-1,2, Pathfinder martian landers (1976 — 1997). The initial values of Euler angles and their derivatives as well as the value of the dynamic oblateness of the Mars have been determined. It was shown that the angle velocity of the Mars rotation has abrupt jumps twice during the martian year, and keeps a constant value during other time. The moments of jumps correspond the such Mars positions on its eccentric orbit when the solar insolation reaches the critical levels.

7. The consistent secular system of equations for the general theory of the Earth's rotation and equations for forward motion of planets and the Moon has been constructed (in the the framework of the problem of construction of a long-term analytic theory of the Earth's rotation).