The IAU Executive Committee has agreed to our proposal for the above mentioned IAU symposium.

Since the discovery of the solar rotation by Galileo Galilei in 1612, the rotation of celestial bodies has remained a topic of interest in Astrophysics. A major revival of the study of stellar rotation has occured over recent years. The organisation of an IAU Symposium on Stellar Rotation now appears to be timely, since the last IAU meeting specifically devoted to rotation was IAU Colloquium 4 "Stellar Rotation" by Arne Slettebak in 1969.

The last years have seen new observations of rotational velocities in solar types stars, in red giants, in intermediate and massive stars, which put new constraints on the evolution of the angular momentum. Anomalies of chemical abundances also constrain the effects of rotation, these are: the Li abundances in low mass stars, the CNO anomalies in red giants, in OB stars and in A- and B-supergiants. Some recent observations in the Galaxy, the LMC and SMC suggest possible differences of v sini and of the related N/C excesses between galaxies. For the Sun, the results on the constancy of the angular velocity in the interior and on the thickness of the tachocline offer major constraints on the hydrodynamics of rotation. The velocities of rotation in binaries are a test of the tidal interaction and of the synchronisation mechanisms. Last but not least, the asymmetric nebulae around Luminous Blue Variables, WR and Be stars, and around planetary nebulae are also signatures of rotational effects and mass loss in these advanced stages.

On the theoretical side, there are new hydrodynamical studies of the various rotational instabilities and of the meridional circulation. There are 2D- and 3D-hydrodynamic simulations, new studies of the synchronisation in binaries and of the interaction between rotation, mass loss, convection and magnetic chromospheric coupling. New models of the evolution of rotating stars are currently being calculated by several groups for low and high mass stars from the MS to the final stages.(We do not intend to cover the theory of star formation and pre-MS evolution because it is a whole subject in itself). The many broad consequences of stellar rotation will be analysed: for the age determinations, the star populations, the chemical yields at low and high metallicities, the nature of the supernovae and the rotation periods of pulsars.

We shall take the opportunity, at this meeting, to honour Dr. Jean-Paul Zahn, who has so much contributed to our understanding of stellar rotation.

This meeting is supported by IAU Division IV (Stars), IAU commission No. 35 "Stellar Constitution" (sponsoring Commission), Commission No. 27 "Variable Stars", Commission No. 29 "Stellar Spectra" and by Commission No. 36 "Theory of Stellar Atmospheres".

Beatriz Barbuy (Brasil); Joergen Christensen-Dalsgaard (Danemark); Philippe Eenens (co-chair, Mexico); Ian Howarth (UK); Gloria Koenigsberger (Mexico); Henny Lamers (The Netherlands); Andre Maeder (co-chair, Switzerland); Sabatino Sofia (USA); Don VandenBerg (Canada); Jean-Paul Zahn (France)

Philippe Eenens (chairman, Guanajuato); Gloria Koenigsberger (UNAM); Jane Arthur (UNAM); Octavio Cardona (INAOE); Luis Corral (IAC); Cesar de la Cruz (Universidad de Veracruz); Filiberto Gonzalez (Guanajuato); Leticia Martinez (Guanajuato); Jaime Noriega (Guanajuato).

The resort of Cancun in Mexico was chosen, because it offers many direct airline connections, excellent conference and accomodation facilities, together with the beauty of Caribbean Sea and the high cultural interest of the Maya sites in the Yucatan Peninsula. An excursion to the famous site of Chichen Itza will be organized on Saturday 16 November.

Participants are expected to arrive in Cancun not later than Sunday 10 November, and to depart from Cancun not earlier than Saturday 16 November 2002.

All participants, including invited speakers and SOC/LOC members, must register. Following the Rules for IAU Sponsored Meetings "participation in Symposia is by invitation of the SOC chairperson. Invitations may be sought by suitably qualified scientists working in the field". If you are interested to participate in the symposium, please fill out the pre-registration form and return it before december 15, 2001, to:

Prof. A. Maeder, co-chairman of the SOC (andre.maeder@obs.unige.ch)

with a copy to the LOC (iau215@astro.ugto.mx)

The scientific programme will consist of invited reviews (35 min) and invited talks (15 min). Oral and poster presentations will be accepted uponreview by the SOC. A list of the invited speakers, who will be contacted over the coming months, and a preliminary programme will begiven in the Second Announcement, to be distributed at the beginning of 2002.

The programme will include the following topics:

I .   OBSERVATIONS OF ROTATING STARS
 Calibrations of rotational velocities 
 Rotation of pre-MS stars 
 Rotation of intermediate and low mass MS stars
 Rotation of red giants, HB and AGB stars
 Rotation of O, B, A stars and supergiants
 Rotation of Be, B[e], LBV and WR stars
 Rotation in binary stars 
 Rotation and pulsations

II .   ROTATION IN RELATION TO ABUNDANCES AND MAGNETIC FIELDS
 Rotation and chemical anomalies in OB stars and supergiants
 Rotation in Am and Ap stars
 Rotation and Li, CNO abundances in low mass stars and red giants
 Observations of rotation and magnetic activity, X-rays
 Braking of rotation by magnetic coupling

III:   ROTATION AND STELLAR PHYSICS
       Stellar interiors
 The instabilities driven by rotation 
 Rotational transport processes
 Internal rotation and magnetic field
 Rotation and pulsations 
       Stellar winds
 Rotation and asymmetric nebulae 
 Stellar winds and rotation
 Disks formation by rotational ejection.
 Be-stars 

 IV:   ROTATION AND STELLAR EVOLUTION
       The Sun
 The internal solar rotation from helioseismology
 Constraints on the physical processes. The tachocline
 Models of solar evolution with rotation
 2-D and 3-D models for solar interior 

       Other stars
 Models for lower and intermediate masses, red giants
 Evolution with rotation for  massive stars and supergiants
 Evolution close to the break-up limit 
 Evolution of rotation in binaries

 V :   FINAL STAGES, NUCLEOSYNTHESIS
  Rotation and WD properties: observations and theory
  Effects of rotation on the chemical abundances and yields
  Pre-supernova evolution with rotation 
  Comparisons with pulsar periods  
  2-D models of supernova explosions 
  Core collapse and gamma-ray bursts  
  Concluding remarks and perspectives 

SOC:
Andre Maeder
Geneva Observatory
Chemin des Mailettes, 51
CH - 1290 SAUVERNY
Switzerland

email: andre.maeder@obs.unige.ch

Philippe Eenens
Dept Astronomia
University of Guanajuato
GUANAJUATO GTO 36000
Mexico

email: eenens@astro.ugto.mx

LOC:
IAU 215
Dept Astronomia
University of Guanajuato
GUANAJUATO GTO 36000
Mexico

email: iau215@astro.ugto.mx
phone: 52-4 732 9607
fax : 52-4 732 0253