[vsnet-chat 7764] Fw: IAU Symposium 289: Advancing the Physics of Cosmic Distances [1st announcement]

[Daisaku NOGAMI]

               F I R S T   A N N O U N C E M E N T

          International Astronomical Union Symposium 289

           "Advancing the Physics of Cosmic Distances"
        http://www.mporzio.astro.it/IAUS289/www/Home.html
                       iaus289 at gmail.com

IAU General Assembly, National Convention Centre, Beijing (China)

                        27-31 August 2012

(For practical information, scroll to the bottom of this announcement.)

** SOUNDBITE: **

Knowing the distance of an astrophysical object is key to
understanding it. However, at present, comparisons of theory and
observations are hampered by precision (or lack thereof) in distance
measurements or estimates. Putting the many recent results and new
developments in relevant subareas into the broader context of the
physics driving cosmic distance determination is the next logical
step, which will benefit from the combined efforts of theorists,
observers and modellers working on a large variety of spatial scales,
and spanning a wide range of expertise. This Symposium will focus on
the physics underlying methods of distance determinations across the
Universe, exploring on the way the various methods employed to define
the milestones along the road. We aim to provide a snapshot of the
field of distance measurement, offering not only up-to-date results
and a cutting-edge account of recent progress, but also full
discussion of the pitfalls encountered and the uncertainties that
remain. We aim to provide a roadmap for future efforts in this field,
both theoretically and observationally.


** SCIENTIFIC ORGANISING COMMITTEE: **

Richard de Grijs    (KIAA, Peking University, China) - co-chair
Giuseppe Bono       (Universit=E2=88=9A=E2=80=A0 Roma Tor Vergata, Italy) -=
 co-chair

Susan Cartwright    (University of Sheffield, UK)
Robin Ciardullo     (Pennsylvania State University, USA)
Andrei Dambis       (Sternberg Astronomical Institute, Russia)
Michael Feast       (University of Cape Town, South Africa)
Wendy Freedman      (Carnegie Observatories, USA)
Wolfgang Gieren     (Universidad de Concepci=E2=88=9A=E2=89=A5n, Chile)
Martin Groenewegen  (Royal Observatory of Belgium, Belgium)
Jeremy Mould        (Swinburne University of Technology, Australia)
Carme Jordi         (Universitat de Barcelona, Spain)
Mark Reid           (Harvard-Smithsonian Center for Astrophysics, USA)
Myung-Hyun Rhee     (Yonsei University, Republic of Korea)
Don VandenBerg      (University of Victoria, Canada)
Rogier Windhorst    (Arizona State University, USA)
Ye Xu               (Purple Mountain Observatory, China)


** SCIENTIFIC RATIONALE: **

Knowing the distance of an astrophysical object is key to
understanding it: without an accurate distance we do not know how
bright it is, how large it is, or even (for long distances) when it
existed. But astronomical distance measurement is a challenging
task. Distances to stars were first measured in 1838 by Bessel, Struve
and Henderson, and accurate distances to other galaxies -- even the
nearest -- date only from the 1950s. This is not really surprising,
since the only information we have about any object beyond our Solar
System is its position (perhaps as a function of time) and its
brightness (as a function of wavelength and time). Yet, from this
unpromising starting point, modern astronomers have developed methods
of measuring distances which can take us from the nearest star to the
most distant galaxy, using techniques that vary from the mundane (the
astronomical equivalent of the surveyor's theodolite) to the exotic
(the bending of light in general relativity, wiggles in the spectrum
of the cosmic microwave background). Nevertheless, the most accurate
optical and near-infrared methods of distance determination, from the
solar neighbourhood to the highest redshifts, in use today rely
heavily on having access to accurate spectroscopy, supplemented by
astrometric measurements in the Milky Way (and slightly beyond).

In 1997, the Hipparcos space mission provided (for the first time) a
significant number of absolute trigonometric parallaxes at