Opening talk of the Conference and acknowledgments.

Concordia has been the third permanent station inland the Antarctic continent since February 2005. It was built jointly by France and Italy in order to offer to the scientific community a platform for research on the antarctic plateau, high in altitude. After the very successful drilling programme EPICA at Dome C, an European project gathering 10 countries and offering the oldest accurate climate archive, many other field of science will benefit from the exceptional properties of the site, namely astronomical researches. This paper provides information on these properties and on the current facilities in terms of building and transport. In addition, it points out the environmental protection and waste management in force at Concordia, in agreement with the Antarctic Treaty and Madrid Protocol.

The importance of CONCORDIA as a perspective site for Antarcticastronomy is being increasingly considered both by the scientistsand the managers of Antarctic research. The data availableindicate that this may be the best site on Earth, and under somerespects even better than space, at least in some observationalbands. Further site testing is needed to make this a generallyheld opinion. Still, operations from CONCORDIA need to be plannedimmediately. SCAR recognises the enormous potential of CONCORDIA,and of the Antarctic plateau in general; so much so that itencourages the international astronomical community to identify aScientific Research Program in Antarctic astronomy andastrophysics to be considered by the national delegates at itsnext general assembly in 2008. The role of ARENA in thepreparation of this proposal should be as relevant as the qualityof the site suggests.

This paper describes STELLA ANTARCTICA, one of the two astronomical projects sponsored by the International Polar Year. 


Hereafter we give a brief history of our contribution to astronomical site testing in Antarctica, at least for thehigh angular resolution in the visible range. The decision to undertake the first site testing at South Pole began one year after a congress organized by French Académie des Sciences, in year 1992. Indeed, in 1993 a meeting took place in Chicagowith the participation of Peter Gillingham, Al Harper and Jean Vernin where each one took the respectiveresponsibility of 1) giving a PhD student, 2) the South Pole infrastructure and 3) the relevant instruments.During winter 1995, thanks to a mast equipped with micro-thermal sensors, we demonstrated (Marks et al., 1996, A&AS, 118, 1)that the first 30 m of the surface layer was disrupted by strong optical turbulence. Then, the year after,15 balloons equipped with micro-thermal probes were successfully launched from South Pole. Marks et al. (1999, A&AS, 134, 161)shown that most of the optical turbulence at South Pole was concentrated within a layer 200 m thick abovethe ice level.From this study, it becomes clear that the noticeable katabatic wind present at South Pole was generatingthis huge surface layer and that is why we oriented our astronomical site characterization towardDôme C.
Our first summer seeing estimations began in 2000, which demonstrated (Aristidi et al., 2003, A&AS, 406, L19 & Aristidi et al., 2005, A&A, 444, 651)that, as expected, the surface wind was much less than at South Pole, and, as a matter of fact, the seeingwas much better, and was even exceptional during the four hours of the afternoon where a seeing of less than 0.5 arcsec was measured. In 2005, the Concordia base was first open during the polar night, and one of us,A. Agabi was able to launch 41 balloons equipped with micro-thermal sensors. A differential image motionmonitor (DIMM) was also setup with success. At mid winter, Agabi et al. (2006, PASP, 118, 344) showed that mostof the optical turbulence came from the first 30 m surface layer and very little from the rest of theatmosphere (1.3 arcsec above 8.5 m and 0.37 arcsec above 30 m).

The Antarctic plateau has superb astronomical seeing above aturbulent boundary layer. This layer has a thickness of between tensof metres and a few hundred metres, depending on the site. We aredeveloping a sonic radar, SNODAR, to measure the turbulence in theboundary layer from 10 to 50 m, and, in particular, to measurethe height of the boundary layer to an accuracy of 1 m.Commercial sonic radars typically have a lower limit of about 10 m, and have 10 m range bins. The results from SNODAR shouldallow a confident assessment of the height at which one must mount atelescope in order to realise the superb free atmosphere seeing fromthe Antarctic plateau, which has been measured at Dome C to be 0.27arcsecs on average, and better than 0.15 arcsecs for 25% of thetime.


The Gattini cameras are two site testing instruments for the measurement of optical sky brightness, large area cloud cover and auroral detection of the night sky above the high altitude Dome C site in Antarctica. The cameras have been operating since installation in January 2006 and are currently at the end of the first Antarctic winter season. The cameras are transit in nature and are virtually identical, both adopting Apogee Alta CCD detectors. By taking frequent images of the night sky we obtain long term cloud cover statistics, measure the sky background intensity as a function of solar and lunar altitude and phase and directly measure the spatial extent of bright aurora if present and when they occur. The full data set will return in December 2006 however a limited amount of data has been transferred via the Iridium network enabling preliminary data reduction and system evaluation. An update of the project is presented together with preliminary results from data taken since commencement of the winter season.

Modeling of astronomically important atmosphericparameters, and the impact these parameters have on instrumentperformance, is a powerful tool for assessing the astronomicalpotential of Antarctic sites. This paper summarizes some of thesignificant findings from a combination of regional climate modelingand adaptive optics simulations. Together with estimates of the skybackground, this work strongly implies that the unique astronomicalpotential of Dome C – work that can be done at no other location – ishigh angular resolution science. In particular, the simulations showthat diffraction limited resolution in the optical is possible with amodest AO system deployed on a telescope mounted above the Antarcticboundary layer. This potential strongly differentiates Dome C fromother sites and suggests a tower-mounted, AO equipped, ~2.5 mclass telescope, located at Dome C, could be the premier visibleimaging observatory in the post-HST era.

A large atmospheric field experiment STABLEDC (STudy of the Atmospheric Boundary Layer Environmental at Dome C plateau station) was held at the Franco-Italian station of Concordia at Dome C during 2004–2005. The aim of the field experiment was to study the processes occurring in the long-lived stable and the weak convective atmospheric boundary layers, observed during winter and summer respectively, and to collect the relevant parameters for the atmospheric models. We used both in situ and ground based remote sensing sensors to monitor the meteorological parameters. The thermal structure of the atmosphere and the diurnal behavior of the height of the atmospheric boundary layer, as seen by a minisodar, for a typical summer and winter day is shown. The behaviour of the surface temperature during the year evidences that, on average, the lowest surface temperatures occur in April and mid-August. Warming events were observed periodically during the winter with temperatures sometimes reaching the summer values. Average temperature profiles for each season are shown. During the winter the temperature strongly decreases in the first 100–200 m. However a detailed analysis of the potential temperature gradients evidence that generally the strongest gradients occur in a narrow layer of 10–40 m. Finally the potential to investigate the fine structure of the PBL with a high resolution minisodar, developed by ISAC/CNR, is discussed.

Due to the recent interest shown by astronomers towards the Antarctic Plateauas a potential site for large astronomical facilities, we assistedin the last years to a strengthening of site testing activities in this region, particularly at Dome C. Most of the results collected so far concern meteorologic parameters and optical turbulence measurements based on different principles using different instruments. At present we have several elements indicating that, above the first $20{-}30$ m, the quality of the optical turbulence above Dome C is better than above whatever other site in the world. The challenging question, crucial to know which kind of facilities to build on, is to establish how much better the Dome C is than a mid-latitude site. In this contribution we will provide some complementary elements and strategies of analysis aiming to answer to this question. We will try to concentrate the attention on critical points, i.e. open questions that still require explanation/attention.

Here we present the first light of the Single Star Scidar (SSS) at Dome C, during January 2005 andthe first results obtained during the winter 2006. We recall the SSS principle, how it is designedto resist to very low temperatures and to be adjusted in a very simple way. No exemple of longperiod of observation can be given since the huge amount of data cannot be sent back to our laboratoryto be offline processed, due to low data transfer available from Dome C. But, a short file is shown,which demonstrates the major contribution of the surface layer to the whole atmosphere opticalturbulence. Almost 300 hours of observations have been taken successfully during winter 2006.

In this paper we present year-round climatological analysis made from radio-sounding measurements and ECMWF Data. And we end up with a generalized conclusion (scientific aspect) from statistical results of site-testing at Concordia concerning the feasibility of the future astronomical exploitation of Dome C.

PAIX, acronym for Photometer AntarctIc eXtinction, is a new photometer which has just been installed at Dome C in December 2006. PAIX consists of a 40 cm telescope equipped with a KAF-0401E CCD detector. The goal is to qualify the site of Dome C and to get continuous observations for making the best from stellar pulsation studies across the HR diagram.

The CEA, in coordination with IPEV and LUAN, will prepare an experiment to study frost formation on surfaces in radiative cooling in the winter. This experiment has been shipped to be installed at Concordia before the 2007 winter period. It will be controlled from Concordia winterover personal, through PC server that will locally archive data from WEBcams and several local heat regulators. This experiment will be used to give recipes on the way to compensate with heaters the radiative cooling from the sky and maintain instrument surfaces at temperature just above icing conditions. The individual regulators proposed in this experiment will be usable as standalone ice protection systems for existing and future telescopes.

Progress in our understanding of solar magnetism and activity rest to a large part on our ability to improve spatial resolutionfor resolving the solar surface magnetic fields fine structure. The solarcorona is permeated by magnetic fields emerging from the sun and, inturn, ejects particules and magnetic field into the heliosphere. It isof prime importance to measure the coronal magnetic field to understand mechanisms at work in the corona. We explain why Dome C isexpected to be an outstanding site for such observations and describethe Solar Brightness Monitor we prepare to probe sky background andaerosols levels at this site. We also discuss coronal observations Dome C could allow to obtain.

DOME C is advocated as being currently the best astronomical site on Earth, with an excellent duty cycle, excellent seeing (provided that the instrumentation is above the $\sim $30 m boundary layer), low scintillation, low infra red background. There is an opportunity for astronomy projects in the coming years at DOME C.We will review here the case for the extrasolar planet searches. Both transit and microlensing searches for extrasolar planets have a niche at DOME C, but the exact performances of such projects are strongly dependent on the true quality of the site. Transiting hot Jupiters could be efficiently detected thanks to the excellent duty cycle at DOME C. The case of hot Neptunes is not clear. Frozen 1–15 Earth mass planets are detectable with dedicatedmicrolensing operation, either by concentrating on a highmagnification events alerted by temperate sites, or a wide fieldimager on a 2 m class telescope to simultaneously detect and monitor microlensing events. In order to run detailed simulations of observations of theseprojects, we have a critical need of seeing statistics, and in particularabout the behavior of the boundary layer above the ice sheet and itsinfluence on the resulting seeing.

This paper discusses the opportunities at Dome C for both photometric and spectroscopic asteroseismology. Dome C has two great advantages in this field: the first is the high percentage of superbly photometric skies; the second is the opportunity for long runs, a necessary requirement for asteroseismology. The potential of Dome C for asteroseismology is compared with existing ground-based networks and a potential spectroscopic networks, as well as with space missions.


Dome C, being one of the summits of the Antarctic plateau, is anexceptional site for astronomy. Its advantages over atemperate-latitude site for a wide range of observations areconsiderable, as well as becoming increasingly appreciated by thescientific community. We discuss what these advantages are, and someof the science possibilities they offer. They fall under fourprincipal regimes: (i) diffraction-limited observations (i.e.λ > 3 µm), (ii) wide-field thermal infrared observations(i.e. λ > 2.2 µm), (iii) when observations areseeing-limited (i.e. from 0.4–3 μm) and (iv) new windows(i.e. in the mid–IR and sub–mm). Each regime offers particularadvantages over corresponding observations made from a temperate site.When more than one of these advantages applies the gains can bepotent.
The science possibilities are many, ranging from solar system science,such as monitoring the global climate of Mars and Venus, to the studyof the distant universe, such as ultra-deep fields to probe theassembly process of galaxies and the search for the “first light”through thermal–IR emission from gamma ray bursters. In this paperwe discuss a range of science opportunities offered by each of theseregimes, making use of a 2 m-class telescope. Such a facility wouldserve as an essential next step in the development of Antarcticastronomy, and the far-reaching possibilities offered by largertelescopes and interferometers on the Antarctic plateau.



The science case for an ELT covers a very wide range of topics fromthe study of exo-planets to fundamental parameters of theUniverse. Here the case is summarised, and areas where an Antarctic sitewould provide advantages or limitations are considered. Simple scalingarguments are used to suggest that a “Moderately Extremely LargeTelescope” (or “MELT”) of order 15–20 m diameter in Antarctica wouldbe capable of carrying out some (but not all) of theobservations currently envisaged for a $\sim $40 m class ELT at atemperate site. It is suggested that any such Antarctic telescopeshould be dedicated to a small number of specific science goals,chosen to complement ELTs at temperate sites.

We present here a study of the Infrared properties ofAsymptoticGiant Branch stars (hereafter AGB) based on existing databases,mainly from space-borne experiments. Preliminary results about Cand S stars are discussed, focusing on the topics for which futureInfrared surveys from Antarctica will be crucial. This kind ofsurveys will help in making more quantitative our knowledge of thelast evolutionary stages of low mass stars, especially for whatconcerns luminosities and mass loss.