In the òÀÜAstronomical YearbookòÀÝ (AY) the ephemerides of the Sun, Moon, major planets and stars computed with the maximum precision in accordance with the resolutions approved by the International Astronomical Union (IAU) are published. The information is also given on various astronomical phenomena – lunar and solar eclipses, planetary configurations, rises and sets of the Sun and Moon, etc. The explanation, contained the examples, illustrates the possibility of the calculation of various ephemerides to any particular time and for the any observation place.

Since issue for 2004 the reform AY is carried out connected to change of ephemerical bases AY (theories of movement of major planets and the Moon, precession-nutation models, the star catalogue) according to Recommendations XXIII and XXIV General assemblies IAU.

In AY for 2004 and 2005 the basis of the calculation of the ephemerides of the Sun, Moon and major planets is the theory DE405/LE405 developed at the JPL (Jet Propulsion Laboratory in Pasadena, Calif., USA) which represent the motion of these bodies with sufficient accuracy for the theoretical researches and the practical applications. Also the fundamental catalog FK6 was used when calculing the stars ephemerides. The ephemerides of the stars which have not in this catalog are based on the catalog HIPPARCOS.

The following improvement are made in òÀÜAstronomical Yearbook for 2006òÀÝ:

• The ephemeride DE405/LE405 for the Sun, the Moon and major planets is replaced on EPM2004 developed at IAA RAS. It is the higher-order divergence of results between theories than accuracy of the data published in AY for these bodies.
• The nutation theory IAU2000 is used instead of IAU1980. The IAU2000 is applied taking into account corrections as the century members to the nutation in longitude and declination, which can be interpreted as the corrections to parameters of precession of theory IAU1976.
• Calculation the sidereal time is made with use òÀÜthe siderial angleòÀÝ (òÀÜthe angle of rotation of the EarthòÀÝ) and new expression for the equation of equinoxes accepted in òÀÜIERS Convention (2003)òÀÝ.
• The shift of average poluse J2000.0 relative to the pole ICRS is taken into account at calculation of elements of the precession-nutation matrix.

In that way the important changes took place in most parts of òÀÜThe Astronomical YearbookòÀÝ.

Since issue for 1997 all ephemeris data are calculated with the aid of òÀÜAEòÀÝ – òÀÜAstronomical YearbookòÀÝ software package created in the laboratory of astronomical yearbooks and altered the corresponding impruvement: the data bases of the ephemerides of planets, of the Sun, Moon and stars were replaced; the some software procedures connected with the calculation and output of the data were modified.

In òÀÜThe Astronomical Yearbook for 2006òÀÝ the calculation of the ephemeris data was carried out by following collaborators of the laboratory of astronomical yearbooks:

• the sidereal time – N.I. Glebova, M.L. Sveshnikov;
• the ephemerides of the geocentric coordinates of the Sun and Moon, the geocentric and heliocentric coordinates of the major planets, osculating elements of the planet orbits, the ephemerides of the position and velocity of the Earth in the barycentric frame, the elements of the precession matrix and of the nutation matrix, the terms by reductions at 0^h terrestrial dynamical time – N.I. Glebova;
• the ephemerides of the Moon (coefficients of the Tchebyshov polynomials), of the lunar crater Mösting A, the ephemeris for physical observations of the Moon, the fundamental arguments of the lunar physical libration, the phases of the Moon, perigee and apogee – N.I. Glebova;
• the seasons and precession values, the planetary configurations – N.I. Glebova;
• the data for the eclipses of the Sun and Moon and transit of Mercury across Sun's disk – M.V. Lukashova;
• the ephemerides for physical observations of the Sun, planets and Saturn's rings – M.L. Sveshnikov;
• the times of rise and set of the Sun and Moon – M.V. Lukashova;
• mean places of stars at J2000.0, the table of the corrections for the orbital motion of stars – M.L. Sveshnikov;
• the terms of reductions for 0^h of sidereal dynamical time, the second order terms of reductions, the mean places of stars, the apparent places of the tenday and circumpolar stars – N.I. Glebova;
• the table for altitudes and azimuths of Polaris and the tables for latitude determinations from observations of Polaris – M.L. Sveshnikov.

The data control of the different part of the Yearbook was carried out by N.I. Glebova, N.K. Omelyanchuk, and I.A. Lebedeva.

The explanation for the Yearbook was subjected to essential edition end reduction fulfilled by N.I. Glebova, M.V. Lukashova, and M.L. Sveshnikov.

The additional information on algorithms of calculation of ephemerides published in AY is given in òÀÜThe Explanatory Supplement to òÀÜthe Astronomical YearbookòÀÝ (òÀÜTransactions of IAA of RASòÀÝ, 2004, vol.10).

The examples in the Explanation were carried out by N.I. Glebova, M.V. Lukashova.

The Explanation in the T_EX was carried out by N.I. Glebova, M.V. Lukashova and N.K. Omelyanchuk. Since 1995 the publication of the òÀÜAstronomical YearbookòÀÝ was became possible with the aid of the òÀÜSystem of the table edition issue SVITAòÀÝ worked out by the collaborations of the astronomical software development technology laboratory. The preparation of the edition of òÀÜThe Astronomical Yearbook for 2006òÀÝ was carry out with the participation of G.A. Necvetaeva, D.A. Ryzhkova.

The original-maket of the Yearbook was prepared in IAA RAS.

Some ephemerides published in Yearbook were inserted in Internet:

• The seasons values, the phases of the Moon, the planetary configurations, the data for the eclipses of the Sun and Moon and transit of Mercury across Sun's disk (N.I. Glebova, M.V. Lukashova) are placed on a site

http://vm-www.ipa.nw.ru/PAGE/ENG/newe.htm

• The list of the observatories coordinates as appendix to Yearbook (M.V. Lukashova, M.L. Sveshnikov) are placed on a site

http://vm-www.ipa.nw.ru/PAGE/EDITION/ENG/AE/appendix.htm

WEB-master – N.I. Alehina.

Appendix: Coordinates of observatories