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The summit of the Antarctic plateau, Dome A, is proving to be an excellent site for optical, NIR, and THz astronomical observations. GATTINI was a wide-field camera installed on the PLATO instrument module as part of the Chinese-led traverse to Dome A in January, 2009. We present here the measurements of sky brightness with the Gattini ultra-large field of view (90 deg x 90 deg) in the photometric B-, V-, and R-bands, cloud cover statistics measured during the 2009 winter season, and an estimate of the sky transparency. A cumulative probability distribution indicates that the darkest 10% of the nights at Dome A have sky brightness of S_B = 22.98, S_V = 21.86, and S_R = 21.68 mag arcsec^{-2}. These values were obtained around the year 2009 with minimum aurora, and they are comparable to the faintest sky brightness at Mauna Kea and the best sites of northern Chile. Since every filter includes strong auroral lines that effectively contaminate the sky brightness measurements, for instruments working around the auroral lines, either with custom filters or with high spectral resolution instruments, these values could be easily obtained on a more routine basis. In addition, we present example light curves for bright targets to emphasize the unprecedented observational window function available from this ground-based site. These light curves will be published in a future paper., 36 pages, 18 figure, submitted to AJ

The Antarctic plateau is one of the best observing sites on the surface of the Earth thanks to its extremely cold, dry, stable and transparent atmosphere conditions. Various astronomical activities are underway there and the Chinese Center for Antarctic Astronomy (CCAA) is dedicated to developing Antarctic astronomy at the highest point, Dome A or the Chinese Kunlun station. So far a large number of images have been collected from a 14.5-cm quad-telescope called the Chinese Small Telescope ARray (CSTAR) and the first two of a trio of 50-cm Antarctic Survey Telescopes (AST3-1 and AST3-2).

Kennicutt, M.C. et. al.-- 17 pages, 3 figures, The Antarctic Roadmap Challenges (ARC) project identified critical requirements to deliver high priority Antarctic research in the 21st century. The ARC project addressed the challenges of enabling technologies, facilitating access, providing logistics and infrastructure, and capitalizing on international co-operation. Technological requirements include: i) innovative automated in situ observing systems, sensors and interoperable platforms (including power demands), ii) realistic and holistic numerical models, iii) enhanced remote sensing and sensors, iv) expanded sample collection and retrieval technologies, and v) greater cyber-infrastructure to process ‘big data’ collection, transmission and analyses while promoting data accessibility. These technologies must be widely available, performance and reliability must be improved and technologies used elsewhere must be applied to the Antarctic. Considerable Antarctic research is field-based, making access to vital geographical targets essential. Future research will require continent- and ocean-wide environmentally responsible access to coastal and interior Antarctica and the Southern Ocean. Year-round access is indispensable. The cost of future Antarctic science is great but there are opportunities for all to participate commensurate with national resources, expertise and interests. The scope of future Antarctic research will necessitate enhanced and inventive interdisciplinary and international collaborations. The full promise of Antarctic science will only be realized if nations act together, The authors recognize the financial support that made the Scan and ARC possible. The Council of Managers of National Antarctic Programs (COMNAP), the Tinker Foundation and the Scientific Committee on Antarctic Research (SCAR) provided the majority of the funding for this project including the costs of travel and participation of invited, non-COMNAP workshop attendees. In-kind support was provided by many COMNAP-Member national Antarctic programmes including Dirección Nacional del Antártico (DNA, Argentina), Australian Antarctic Division (AAD, Australia), Programa Antártico Brasileiro (PROANTAR, Brazil), Instituto Antártico Chileno (INACH, Chile), Polar Research Institute of China (PRIC, China), Instituto Antártico Ecuatoriano (INAE, Ecuador), Institut Polaire Français Paul Emile Victor (IPEV, France), Alfred Wegener Institute (AWI, Germany), National Institute of Polar Research (NIPR, Japan), Korea Polar Research Institute (KOPRI, Republic of Korea), Antarctica New Zealand (New Zealand), Arctic and Antarctic Research Institute (AARI, Russia), Spanish Polar Committee (CPE, Spain), British Antarctic Survey (BAS, UK), and the US National Science Foundation (NSF, USA)

The Ring Imaging Cherenkov detectors of LHCb will use pixel Hybrid Photon Detectors to measure the spatial position of Cherenkov photons. The first six pre-production photon detectors have been tested in a beam, together with prototypes of the on-detector electronics. The tests were performed at CERN using 10 GeV / c pions together with an N2 gas radiator as a source of Cherenkov light. With 1.1 m of radiator, around 10 photoelectrons were detected per track. The single-photon Cherenkov angle resolution was measured to be 1.66 ± 0.03 mrad, which is dominated by the pixelisation of the photon detector in the test-beam set-up. Both numbers agree with expectations. © 2007 Elsevier B.V. All rights reserved.

An array of Multi-anode Photomultiplier Tubes (MaPMT) was evaluated for use in the LHCb Ring Imaging Cherenkov (RICH) detectors using a prototype RICH detector in a charged particle beam. The MaPMT performance was measured with different radiator gases with and without lenses. The performance of the MaPMTs in terms of photon yield and pixel cross-talk is presented. (c) 2005 Elsevier B.V. All rights reserved.

Astronomers have always sought the best sites for their telescopes. Antarctica, with its high plateau reaching to above 4,000 metres, intense cold, exceptionally low humidity and stable atmosphere, offers what for many forms of astronomy is the ultimate observing location on this planet. While optical, infrared and millimetre astronomers are building their observatories on the ice, particle physicists are using the ice itself as a detector and exploration of the terahertz region is being conducted from circumpolar long-duration balloons. Remarkable astronomical discoveries are already coming out of Antarctica, and much, much more is just around the corner.

While the summit of the Antarctic Plateau has long been expected to harbor the best ground-based sites for terahertz (THz) frequency astronomical investigations, it is only recently that direct observations of exceptional THz atmospheric transmission and stability have been obtained. These observations, in combination with recent technological advancements in astronomical instrumentation and autonomous field platforms, make the recognition and realization of terahertz observatories on the high plateau feasible and timely. Here, we will explore the context of terahertz astronomy in the era of Herschel, and the crucial role that observatories on the Antarctic Plateau can play. We explore the important scientific questions to which observations from this unique environment may be most productively applied. We examine the importance and complementarity of Antarctic THz astronomy in the light of contemporary facilities such as ALMA, CCAT, SOFIA and (U)LDB ballooning. Finally, building from the roots of THz facilities in Antarctica to present efforts, we broadly highlight future facilities that will exploit the unique advantages of the Polar Plateau and provide a meaningful, lasting astrophysical legacy.

Antarctic astronomical site-testing has been conducted using autonomous self-powered observatories for more than a decade (the AASTO at South Pole, the AASTINO at Dome C, and PLATO at Dome A/Dome F). More recently autonomous (PLATO) observatories have been developed and deployed to support small-scale scientific instruments, such as HEAT, a 0.6 m aperture terahertz telescope at Ridge A, and AST3, a 0.5 m optical telescope array at Dome A. This paper reviews the evolution of autonomous Antarctic astronomical observatories, and discusses the requirements and implications for observatories that will be needed for future larger-scale facilities.

We carried out the first seeing measurements at Dome Fuji in the 2010–2011 austral summer. From these observations, we found that the summer seeing at Dome Fuji was 1.2″ (mean), 1.1″ (median), 0.83″ (25th percentile) and 1.5″ (75th percentile), respectively. We also found that the seeing changed continuously and had a minimum around 0.7″ at ~18:00 hours daily. We compared the seeing with some weather parameters obtained from the 16 m mast, and found that the seeing had good correlations with atmosphere temperature and wind shear. These results suggest that the seeing is degraded by turbulence near the surface boundary layer. Because the data were obtained only over a short duration in summer, the general characteristics of Dome Fuji's seeing could not be evaluated. We plan to observe the seeing in winter with a stand-alone DIMM telescope. This new DIMM, which we named the Dome Fuji Differential Image Motion Monitor (DF–DIMM), will be installed at Dome Fuji in January 2013.

In 2008 January the 24th Chinese expedition team successfully deployed the Chinese Small Telescope ARray (CSTAR) to Dome A, the highest point on the Antarctic plateau. CSTAR consists of four 14.5cm optical telescopes, each with a different filter (g, r, i and open) and has a 4.5°×4.5° field of view (FOV). Based on the CSTAR data, initial statistics of astronomical observational site quality and light curves of variable objects were obtained. To reach higher photometric quality, we are continuing to work to overcome the effects of uneven cirrus cloud cirrus, optical “ghosts” and intra-pixel sensitivity. The snow surface stability is also tested for further astronomical observational instrument and for glaciology studies.

At the summit of the Antarctic plateau, Dome A offers an intriguing location for future large scale optical astronomical observatories. The Gattini Dome A project was created to measure the optical sky brightness and large area cloud cover of the winter-time sky above this high altitude Antarctic site. The wide field camera and multi-filter system was installed on the PLATO instrument module as part of the Chinese-led traverse to Dome A in January 2008. This automated wide field camera consists of an Apogee U4000 interline CCD coupled to a Nikon fisheye lens enclosed in a heated container with glass window. The system contains a filter mechanism providing a suite of standard astronomical photometric filters (Bessell B, V, R) and a long-pass red filter for the detection and monitoring of airglow emission. The system operated continuously throughout the 2009, and 2011 winter seasons and part-way through the 2010 season, recording long exposure images sequentially for each filter. We have in hand one complete winter-time dataset (2009) returned via a manned traverse. We present here the first measurements of sky brightness in the photometric V band, cloud cover statistics measured so far and an estimate of the extinction.

SCAR, the Scientific Committee on Antarctic Research, is, like the IAU, a committee of ICSU, the International Council for Science. For over 30 years, SCAR has provided scientific advice to the Antarctic Treaty System and made numerous recommendations on a variety of matters. In 2010, Astronomy and Astrophysics from Antarctica was recognized as one of SCAR's five Scientific Research Programs. Broadly stated, the objectives of Astronomy & Astrophysics from Antarctica are to coordinate astronomical activities in Antarctica in a way that ensures the best possible outcomes from international investment in Antarctic astronomy, and maximizes the opportunities for productive interaction with other disciplines. There are four Working Groups, dealing with site testing, Arctic astronomy, science goals, and major new facilities. Membership of the Working Groups is open to any professional working in astronomy or a related field., Astrophysics from Antarctica (S288), August, 2012, Beijing, China, Series: Proceedings of the International Astronomical Union

Despite the absence of artificial light pollution at Antarctic plateau sites such as Dome A, other factors such as airglow, aurorae, and extended periods of twilight have the potential to adversely affect optical observations. We present a statistical analysis of the airglow and aurorae at Dome A using spectroscopic data from Nigel, an optical/near-IR spectrometer operating in the 300-850 nm range. These data complement photometric images from Gattini, a wide-field (90 degrees) CCD camera with B, V, and R filters, allowing the background sky brightness to be disentangled from the various airglow and auroral emission lines. The median auroral contribution to the B, V, and R photometric bands is found to be 22.9, 23.4, and 23.0 mag arcsec(-2), respectively. Auroral emissions most frequently occur between 10-23 hr local time, when up to 50% of observations are above airglow-level intensities. While infrequent, the strongest emissions detected occurred in the hours just prior to magnetic midnight. We are also able to quantify the amount of annual dark time available as a function of wavelength, as well as in the standard BV R photometric bands. On average, twilight ends when the Sun reaches a zenith distance of 102.6 degrees.

The high altitudes and extremely low temperatures of the Antarctic plateau result in an exceedingly low atmospheric water vapor content. In this article we estimate the precipitable water vapor at Dome A using optical spectra of the diffuse solar irradiance in the zenith direction. The spectra were obtained from the Nigel spectrometer at Dome A during 2009. We find that the Nigel spectra contain sufficient information to extract daily average water vapor estimates, which agree with satellite observations to within +/- 0.22 mm. Finally, we use these water vapor estimates to model the optical and near-IR transmission (between 700 nm and 2.5 mu m) of Dome A to demonstrate significant advantages gained in this wavelength range and compare it with that of Paranal and Chajnantor, two midlatitude observatories.

Antihydrogen spectroscopy promises precise tests of the symmetry of matter and antimatter, and can possibly offer new insights into the baryon asymmetry of the universe. Antihydrogen is, however, difficult to synthesize and is produced only in small quantities. The ALPHA collaboration is therefore pursuing a path towards trapping cold antihydrogen to permit the use of precision atomic physics tools to carry out comparisons of antihydrogen and hydrogen. ALPHA has addressed these challenges. Control of the plasma sizes has helped to lower the influence of the multipole field used in the neutral atom trap, and thus lowered the temperature of the created atoms. Finally, the first systematic attempt to identify trapped antihydrogen in our system is discussed. This discussion includes special techniques for fast release of the trapped anti-atoms, as well as a silicon vertex detector to identify antiproton annihilations. The silicon detector reduces the background of annihilations, including background from antiprotons that can be mirror trapped in the fields of the neutral atom trap. A description of how to differentiate between these events and those resulting from trapped antihydrogen atoms is also included.

The domes, or local elevation maxima, on the Antarctic plateau provide a unique opportunity for ground-based astronomy in that the turbulent boundary layer is so thin that a telescope on a small tower can be in the free atmosphere, i.e., the portion of the atmosphere in which the turbulence is decoupled from the effect of the Earth's surface. There, it can enjoy a free atmosphere which itself appears to offer superior conditions to that of temperate sites. This breaks the problem of characterizing the turbulence at Antarctic plateau sites into two separate tasks: determining the variability, distribution and thickness of the boundary layer, and characterizing the free atmosphere. In this article we tackle the first of these tasks using a high-resolution, low minimum sample height sonic radar (SODAR) called Snodar that has been specifically designed to characterize the Antarctic bound- ary thickness and structure. Snodar delivers a vertical resolution of 0.9 m, with a minimum sampling height of 8 m. Snodar sampled the first 180 m of the atmosphere with 0.9 m resolution every 10 s at Dome A, Antarctica between 2009 February 4 and 2009 August 18. The median thickness of the boundary layer over this period was 13.9 m, with the 25th and 75th percentiles at 9.7 m and 19.7 m, respectively. The data collected from Dome A also show that, while the boundary layer can be stable for several hundred hours at a time, it can also be highly variable and must be sampled on the time scale of minutes to properly characterize its thickness.

We present the first direct measurements of the terahertz atmospheric transmission above Dome A, the highest point on the Antarctic plateau at an elevation of 4.1 km. The best-quartile atmospheric transmission during the Austral winter is 80% at a frequency of 661 GHz (453 μm), corresponding to a precipitable water vapor column of 0.1 mm. Daily averages as low as 0.025 mm were observed. The Antarctic atmosphere is very stable, and excellent observing conditions generally persist for many days at a time. The exceptional conditions over the high Antarctic plateau open new far-infrared spectral windows to ground-based observation. These windows contain important spectral-line diagnostics of star formation and the interstellar medium which would otherwise only be accessible to airborne or space telescopes. Online material: color figures

Construction of PILOT at the existing French/Italian Con- cordia Station at Dome C in Antarctica would bring about major bene- ts for the astronomical research activities of the European and interna- tional astronomical communities. Because of these potential benets, it is proposed that the PILOT Project move into Phase B|the Prelim- inary Design Phase. The output from the study will be a Conceptual Design Report allowing policy makers and their advisors to prepare relevant strategic decisions for the detailed development (nal design), manufacturing and installation of the PILOT astronomical research infrastructure at Dome C.

Site testing data provides an essential part of the justiflcation for funding any new astronomical facility by deflning the technological design and determining the telescope performance, thus allowing the scientiflc objectives to be prioritised. Here we review the current sta- tus of site testing at Dome C by examining the range of instruments that have been, or are planned to be, deployed to the site. We then investigate in more detail preliminary data which has so far proven crucial for telescope design, data for which discrepancies exist between two or more instruments, and required data for which there are no cur- rent plans to obtain. We discuss the implications of this data on the technical design, expected performance, and the scientiflc capabilities for a 2.5 m class optical/infrared telescope. Finally, we identify the site parameters that require further study, and deflne the experiments necessary to determine these parameters.

The THz spectral region includes a number of important transitions which allow us to trace the evolution of the interstellar medium. Because of the opacity of the atmosphere in this spectral range, the best sites for ground-based THz observations are on the Antarctic Plateau; of these sites, Dome A is expected to be the best. THz survey science can be carried out with small telescopes, easing logistical constraints. By deploying a submillimetre-wave tipper/ telescope to Dome A, we have trialled several technologies for such an instrument, and we are able to test whether the site quality is sufficient for THz surveys.

PLATO is a fully-robotic observatory designed for operation in Antarctica. It generates its own electricity (about 1 kW), heat (sufficient to keep two 10-foot shipping containers comfortably above 0°C when the outside temperature is at -70°C), and connects to the internet using the Iridium satellite system (providing ~30 MB/day of data transfer). Following a successful first year of operation at Dome A during 2008, PLATO was upgraded with new instruments for 2009.

We compare the merits of potential observatory sites on the Antarctic Plateau, in regard to the boundary layer, cloud cover, free atmosphere seeing, aurorae, airglow, and precipitable water vapour. We find that (a) all Antarctic sites are likely compromised for optical work by airglow and aurorae; (b) Dome A is the best existing site in almost all respects; (c) there is an even better site (“Ridge A”) 150 kms SW of Dome A; (d) Dome F is a remarkably good site except for aurorae; (e) Dome C probably has the least cloud cover of any of the sites, and might be able to use a predicted `OH hole' in the Spring.

In January 2005, members of a Chinese expedition team were the first humans to visit Dome A on the Antarctic plateau, a site predicted to be one of the very best astronomical sites on earth. In 2006, the Chinese Center for Antarctic Astronomy (CCAA) was founded to promote the development of astronomy in Antarctica, especially at Dome A. CCAA has since taken part in two traverses to Dome A, organized by the Polar Research Institute of China (PRIC), in the austral summers of 2007/2008 and 2008/2009. These traverses resulted in the installation of many site - testing and science instruments, supported by the PLATO observatory. The Chinese Small Telescope ARray (CSTAR) has produced excellent results from Dome A. Our future plans include further site - testing work, and the following full-scale science instruments: three 0.5-m Antarctic Schmidt Telescopes (AST3), and a proposed 4-m telescope for wide-field infrared high spatial-resolution surveys. The first AST3 telescope is under construction and is scheduled for installation in 2011

The Phase A design study of PILOT–the Pathfinder for an International Large Optical Telescope–has demonstrated that a wide-field 2.5 m optical/IR telescope can be constructed at Concordia for a reasonable cost. There are no technical “show stoppers”, and the cost of logistics is also quantifiable and reasonable. A strong science case has been developed and published as three separate papers. In order to proceed further, the next step is to undertake a detailed design study and identify potential manufacturers.

SUMMARY We have characterised a small, high-efficiency diesel generator selected to power remote experiments on the Antarctic plateau at altitudes of up to 5000 m. We describe the design of an environmental chamber to simulate these high altitudes and present an experimental investigation of the engine operation at high altitude on Jet A-1, comparing this to the engine’s performance at sea level. Although attention must be paid to the provision of adequate cooling, no modification to the engine itself is required. Our final system provides very high reliability and produces 1500 W of electrical power with a fuel consumption of 280 g kWh � 1 . A bank of ultracapacitors is used to start the engine in the cold environment of Antarctica. We describe the low-temperature operation and survival tests that we performed on the ultracapacitors and the engine. Copyright r 2009 John Wiley & Sons, Ltd.

The PLATeau Observatory (PLATO) is an automated self-powered astrophysical observatory that was deployed to Dome A, the highest point on the Antarctic plateau, in 2008 January. PLATO consists of a suite of site-testing instruments designed to quantify the benefits of the Dome A site for astronomy, and science instruments designed to take advantage of the unique observing conditions. Instruments include CSTAR, an array of optical telescopes for transient astronomy; Gattini, an instrument to measure the optical sky brightness and cloud cover statistics; DASLE, an experiment to measure the statistics of the meteorological conditions within the near-surface layer; Pre-HEAT, a submillimeter tipping radiometer measuring the atmospheric transmission and water vapor content and performing spectral line imaging of the Galactic plane; and Snodar, an acoustic radar designed to measure turbulence within the near-surface layer. PLATO has run completely unattended and collected data throughout the winter 2008 season. Here we present a detailed description of the PLATO instrument suite and preliminary results obtained from the first season of operation.

The unique atmospheric characteristics found at Dome C on the Antarctic plateau offer significant advantages for the operation of adaptive optics systems. An analysis is presented here comparing the performance of adaptive optics systems on telescopes located at Dome C with similar systems located at a mid-latitude site. The large coherence length, wide isoplanatic angle, and long coherence time of the Dome C atmosphere allow an adaptive optics system located there to correct to high order, observe over wide fields and use faint guide stars, resulting in a lower total wavefront error and a significant increase in sky coverage factor than can be achieved at a typical mid-latitude site. While the same performance could in principle be achievable at mid-latitude sites, this would only occur under exceptionally stable atmospheric conditions that are likely to occur on only a few nights per year.

Dome A, the summit of the Antarctic plateau, is expected to have even better atmospheric conditions for ground-based astronomy than Dome C. However, the logistical constraints are very stringent. Current instrumentation at Dome A exemplifies the requirements im- posed by these constraints. Future instrumentation and infrastructure will exploit the qualities of the site much more fully.

The proposed design for PILOT is a general-purpose, wide-field 1 degree 2.4m, f/10 Ritchey-Chretien telescope, with fast tip-tilt guiding, for use 0.5-25 microns. The design allows both wide-field and diffraction-limited use at these wavelengths. The expected overall image quality, including median seeing, is 0.28-0.3" FWHM from 0.8-2.4 microns. Point source sensitivities are estimated., 4 pages, Proceedings of 2nd ARENA conference 'The Astrophysical Science Cases at Dome C', Potsdam, 17-21 September 2007

In this paper we review the progress towards the deployment of a large "PILOT-like" telescope at Concordia Station, Dome C. PILOT is a proposed 2.4 m optical/IR telescope that will cost in excess of EUR 10 m, and is thus representative of the scale of facility that will transform Concordia into a significant international observatory. A design study of PILOT, funded by the Australian government, is currently underway. We describe the current status of this design study, and discuss the implications that major international projects such as PILOT hold for the future of Antarctic astronomy at Concordia.

The expectation that exceptional conditions for astronomy would be found at Dome C on the high Antarctic plateau has motivated a coordinated effort by a number of international teams to comprehensively measure the atmospheric conditions at this site. This paper presents an overview of the current status of site testing at Dome C. We discuss the past, present, and planned instrumentation, the main results obtained to date, and the implications of these results.

PILOT is proposed as a partnership between Australia and Europe to develop a 2.4 m optical/infrared telescope for Dome C, Antarctica. Funding for a detailed designed study is being sought from Australian sources, with a view to commencing construction in early 2008. The current “strawman” design is for an f/10 dual Nasmyth configuration with provision for both a silicon carbide fast tip-tilt secondary mirror for the thermal infrared, and an adaptive secondary mirror to achieve diffraction-limited imaging at wavelengths as short as V -band.

The Antarctic plateau has superb astronomical seeing above a turbulent boundary layer. This layer has a thickness of between tens of metres and a few hundred metres, depending on the site. We are developing a sonic radar, SNODAR, to measure the turbulence in the boundary layer from 10 to 50 metres, and, in particular, to measure the height of the boundary layer to an accuracy of 1 metre. Commercial sonic radars typically have a lower limit of about 10 metres, and have 10 metre range bins. The results from SNODAR should allow a confldent assessment of the height at which one must mount a telescope in order to realise the superb free atmosphere seeing from the Antarctic plateau, which has been measured at Dome C to be »0.3 arcsecs.

Antarctic and Southern Ocean science is vital to understanding natural variability, the processes that govern global change and the role of humans in the Earth and climate system. The potential for new knowledge to be gained from future Antarctic science is substantial. Therefore, the international Antarctic community came together to ‘scan the horizon’ to identify the highest priority scientific questions that researchers should aspire to answer in the next two decades and beyond. Wide consultation was a fundamental principle for the development of a collective, international view of the most important future directions in Antarctic science. From the many possibilities, the horizon scan identified 80 key scientific questions through structured debate, discussion, revision and voting. Questions were clustered into seven topics: i) Antarctic atmosphere and global connections, ii) Southern Ocean and sea ice in a warming world, iii) ice sheet and sea level, iv) the dynamic Earth, v) life on the precipice, vi) near-Earth space and beyond, and vii) human presence in Antarctica. Answering the questions identified by the horizon scan will require innovative experimental designs, novel applications of technology, invention of next-generation field and laboratory approaches, and expanded observing systems and networks. Unbiased, non-contaminating procedures will be required to retrieve the requisite air, biota, sediment, rock, ice and water samples. Sustained year-round access to Antarctica and the Southern Ocean will be essential to increase winter-time measurements. Improved models are needed that represent Antarctica and the Southern Ocean in the Earth System, and provide predictions at spatial and temporal resolutions useful for decision making. A co-ordinated portfolio of cross-disciplinary science, based on new models of international collaboration, will be essential as no scientist, programme or nation can realize these aspirations alone.

Astronomers have always sought the very best locations for their telescopes. From observatories in city centres, astronomers moved first to nearby mountain tops, then to remote sites in distant countries, to aircraft, and into space. In the past decade we have come to realize that the best astronomical observing conditions on the surface of the earth are to be found on the Antarctic plateau. The combination of high altitude, low temperature, low absolute humidity, low wind and extremely stable atmosphere offers astronomers gains in sensitivity and measurement precision that can exceed two orders of magnitude over even the best temperate sites. In addition, spectral windows are opened up – particularly in the far-infrared and terahertz regions – that are otherwise only accessible from high-flying aircraft or from space. Established and highly successful telescopes at the South Pole are soon to be joined by a new generation of facilities at Concordia Station, including large telescopes and interferometers. It has even been suggested that the largest optical telescopes currently proposed, with diameters of up to 100 m, might achieve their science goals at a lower overall cost if they are built on the Antarctic plateau rather than at a temperate site. Such telescopes offer the possibility of not only detecting earth-like planets in other star systems, but also of analysing their atmospheres spectroscopically.

Many methods have been proposed for the detection of exoplanets. The minimum detectable planetary size and mass, and the maximum distance from us at which exoplanets are observable, are determined by both technological and environmental constraints. The unique atmospheric conditions found at Dome C offer significant advantages. Using what is now known about the turbulence profile of the atmosphere above Antarctic plateau sites, we explore the potential these sites offer for detecting exoplanets around nearby stars using various methods.

Dome C, Antarctica, (75 south, 123 east, 3250 m) is one of the coldest and driest locations on Earth, with exceptionally low winds throughout the atmosphere. It therefore has the potential to be an ideal site for astronomical observations. It is also an excellent site for the validation of satellite instruments. A Fourier transform infrared interferometer was deployed at Dome C during two austral summer seasons (2003 January and 2003 December/2004 January) for the purpose of acquiring satellite validation data. However, these data are also useful for understanding the infrared characteristics of the atmosphere for future astronomical experiments at Dome C. The Polar Atmospheric Emitted Radiance Interferometer measured the downwelling infrared radiance from the atmosphere (sky brightness) from 3 to 20 mm. Over 100 radiosondes were also launched during this time period. Typical measured values of the sky brightness in the clearest portions of the M, N, and Q bands are 0.9, 43, and 310 Jy arcsec 2 , respectively. The lowest measured values of sky brightness within these bands are 0.4, 34, and 200 Jy arcsec 2 . The spectral region of the Q band from about 18.7 to 19 mm is expected to be an excellent window for observations made from the Antarctic Plateau. The sky brightness has been measured between 10.60 and 11.30 m mi n theN band for comparisons to earlier studies at South Pole Station; the values in this band are similar to those in the 8.20-8.40 mm band. For the period of time covered by our observations, the sky brightness in the dark portions of the N band was less than about 50-60 Jy arcsec 2 for about 10% of the time, and less than about 75 Jy arcsec 2 for about 50% of the time. During a 5 day period of clear skies, the mean sky brightness was 47.7 Jy arcsec 2 , with a variation about this mean of 4.4 Jy arcsec 2 (1 j). Calculations of the summertime atmospheric transmission under clear skies over Dome C show that portions of the M, N, and Q bands have transmission greater than 95%, with some spectral regions greater than 99%.

PILOT (Pathfinder for an International Large Optical Telescope) is a proposed 2 m class optical/infrared telescope to be sited at Dome C on the Antarctic plateau. Recent site testing results from Dome C have shown remarkable ground level seeing, a large isoplanatic angle, and a long atmospheric coherence time. These factors significantly improve the resolution and increase the capabilities of adaptive optics systems. Additionally, the low sky emission at Dome C gives a significant increase in infrared sensitivity compared to typical mid-latitude sites. PILOT is envisaged as a winterised version of a commercially available 2 m class telescope, with a simple low cost dome (sufficient for the low ground level wind speeds), and a tip-tilt and/or a deformable secondary mirror. A number of science cameras covering the visible to the sub-millimetre are being considered.

The cold, dry and stable air above the summits of the Antarctic plateau provides the best ground-based observing conditions from optical to sub-mm wavelengths to be found on the Earth. PILOT is a proposed 2 m telescope, to be built at Dome C in Antarctica, able to exploit these conditions for conducting astronomy at optical and infrared wavelengths. While PILOT is intended as a pathfinder towards the construction of future grand-design facilities, it will also be able to undertake a range of fundamental science investigations in its own right. This paper provides the performance specifications for PILOT, including its instrumentation. It then describes the kinds of science projects that it could best conduct. These range from planetary science to the search for other solar systems, from star formation within the Galaxy to the star formation history of the Universe, and from gravitational lensing caused by exo-planets to that produced by the cosmic web of dark matter. PILOT would be particularly powerful for wide-field imaging at infrared wavelengths, achieving near-diffraction limited performance with simple tip-tilt wavefront correction. PILOT would also be capable of near-diffraction limited performance in the optical wavebands, as well be able to open new wavebands for regular ground based observation; in the mid-IR from 17 to 40 microns and in the sub-mm at 200 microns., 74 pages, 14 figures, PASA, in press

The AASTINO (Automated Astrophysical Site Testing International Observatory) is a remote laboratory that has been operating at Dome C station on the Antarctic plateau since January 2003. It is designed to run throughout the Antarctic winter without intervention, and to collect data on the astronomical qualities of the site. A Stirling engine and a pair of solar panels power the observatory. Command, control and communication is via the Iridium satellite network. A supervisor computer system controls all aspects of engine and power source management, communications, instrument control, and data collection. The AASTINO system is designed with the capability to run completely autonomously in the event of communications failure.

The astronomical seeing from the Antarctic high plateau site Dome C has been a matter of speculation for over a decade. During 2004 we made the first wintertime measurements of the seeing using a Multi Aperture Scintillation Sensor (MASS), a device that is well-suited for automated unattended operation. The mean seeing was found to be 0.27 arcsec, and the seeing is better than 0.15 arcsec for 25% of the time. These extraordinarily low levels of turbulence make Dome C a superb site for future optical and infrared telescopes.

The high plateau that covers half of the continent of Antarctica contains the best astronomical observing sites on Earth. The infrared sky background is low, the precipitable water vapour is low, the sub-millimetre sky opacity is low, the winds are low, the atmosphere is exceedingly clear and stable, it never rains, there is no dust, it is geological stable, and the seeing at some sites, notably Dome C, is superb. The turbulence prole in the atmosphere is benecial for adaptive optics, with fewer actuators and fewer deformable mirrors being required, and with signicant correction being possible at visible wavelengths. For projects that require continuous monitoring, e.g., planet detection through micro-lensing, a single robotic telescope in Antarctica can replace a network of 4n6 telescopes placed around the world at mid-latitude sites. For many projects requiring large apertures, a given size telescope in Antarctica will outperform a telescope of 2n3 times the aperture at a mid-latitude site. We review what is known about the site conditions, and outline some of the issues involved with designing robotic telescopes to work in Antarctica.

We have developed a 350 μm radiometer to perform automated site testing in remote regions of Antarctica. In summer 2000–2001 the instrument operated at Concordia, a new station under construction at Dome C on the Antarctic Plateau. We present the results, and compare them with the atmospheric opacity measured at the South Pole in the same five-week period. During these five weeks, observing conditions at Dome C were, on average, substantially better than those at the South Pole.

We report the results of observations of the fine-structure emission lines (C ) 158 µ ma nd (O )6 3µm using FIFI on the Kuiper Airborne Observatory (KAO) and the Long Wavelength Spectrometer (LWS) on board ISO, towards the molecular cloud associated with the stellar cluster Trumpler 14 (Tr 14) in the Carina Nebula. These data are compared with selected CO and CS transitions obtained with the SEST as well as IRAS and MSX images to produce a detailed view of the morphology and the physical conditions prevailing in the photodissociation region (PDR) at the interface between the ionized gas and the molecular dust lane. The relative intensity distribution observed for the various tracers is consistent with the stratification expected for a molecular cloud seen edge-on and exposed to a radiation field of ≈10 4 G0, which is dominated by the most massive stars of Tr 14. The grain photoelectric heating efficiency, � , is estimated to be ≈5 × 10 −3 and is comparable to other galactic PDRs. The molecular gas has a complicated velocity structure with a high velocity dispersion resulting from the impact of the stellar winds arising from Tr 14. There is evidence of small-scale clumping with a very low volume filling factor. Despite the rich concentration of massive O stars in Tr 14 we find that the parameters of the PDR are much less-extreme than those of the Orion and M 17 massive star-forming regions.

The statistics and dynamics of the atmospheric seeing at the South Pole have been studied over a period of 101 days in winter. These measurements have been made with the first fully autonomous dierential image motion monitor, the A-DIMM. The analysis shows an average seeing of 1:9 00 with a standard deviation of 0:6 00 . The extensive set of data has allowed the study of the seeing time variations, showing that the seeing varies by a factor of two within a characteristic time of 2 hours.

To better understand the environment surrounding CO emission clumps in the Keyhole Nebula, we have made images of the region in H2 1-0 S(1) (2.122 um) emission and polycyclic aromatic hydrocarbon (PAH) emission at 3.29 um. Our results show that the H2 and PAH emission regions are morphologically similar, existing as several clumps, all of which correspond to CO emission clumps and dark optical features. The emission confirms the existence of photodissociation regions (PDRs) on the surface of the clumps. By comparing the velocity range of the CO emission with the optical appearance of the H2 and PAH emission, we present a model of the Keyhole Nebula in which the most negative velocity clumps are in front of the ionization region, the clumps at intermediate velocities are in it, and those which have the least negative velocities are at the far side. It may be that these clumps, which appear to have been swept up from molecular gas by the stellar winds from eta Car, are now being over-run by the ionization region and forming PDRs on their surfaces. These clumps comprise the last remnants of the ambient molecular cloud around eta Car.

The near infrared sky spectral brightness has been measured at the South Pole with the Near Infrared Sky Monitor (NISM) throughout the 2001 winter season. The sky is found to be typically more than an order of magnitude darker than at temperate latitude sites, consistent with previous South Pole observations. Reliable robotic operation of the NISM, a low power, autonomous instrument, has been demonstrated throughout the Antarctic winter. Data analysis yields a median winter value of the 2.4μm (Kdark) sky spectral brightness of ˜120μJy arcsec−2 and an average of 210 ± 80μJy arcsec−2. The 75%, 50%, and 25% quartile values are 270 ± 100, 155 ± 60, and 80 ± 30μJy arcsec−2, respectively.

We present spectral line images of [CI] 809 GHz, CO J=1-0 115 GHz and HI 1.4 GHz line emission, and calculate the corresponding C, CO and H column densities, for a sinuous, quiescent Giant Molecular Cloud about 5 kpc distant along the l=328{\deg} sightline (hereafter G328) in our Galaxy. The [CI] data comes from the High Elevation Antarctic Terahertz (HEAT) telescope, a new facility on the summit of the Antarctic plateau where the precipitable water vapor falls to the lowest values found on the surface of the Earth. The CO and HI datasets come from the Mopra and Parkes/ATCA telescopes, respectively. We identify a filamentary molecular cloud, ~75 x 5 pc long with mass ~4 x 10E4 Msun and a narrow velocity emission range of just 4 km/s. The morphology and kinematics of this filament are similar in CO, [CI] and HI, though in the latter appears as self-absorption. We calculate line fluxes and column densities for the three emitting species, which are broadly consistent with a PDR model for a GMC exposed to the average interstellar radiation field. The [C/CO] abundance ratio averaged through the filament is found to be approximately unity. The G328 filament is constrained to be cold (Tdust < 20K) by the lack of far-IR emission, to show no clear signs of star formation, and to only be mildly turbulent from the narrow line width. We suggest that it may represent a GMC shortly after formation, or perhaps still be in the process of formation., Comment: 29 pages, 5 figures. Accepted for publication in The Astrophysical Journal (2014)

Over the past few years, site-testing at the South Pole has revealed conditions that are uniquely favourable for infrared astronomy. In particular, the exceptionally low sky brightness throughout the near and mid-infrared leads to the possibility of a modest-sized telescope achieving comparable sensitivity to that of existing 8–10 metre class telescopes. An 8 metre Antarctic telescope, if constructed, would yield performance that would be unrivalled until the advent of the NGST. In this paper we review the scientific potential of infrared telescopes in Antarctica, and discuss their complementarity with existing 8–10 metre class telescopes and future proposed space telescopes. In particular, we discuss the role that a 2 metre class infrared telescope plays in future plans for the development of an observatory on the Antarctic plateau.

We have used the SPIREX telescope to conduct a wide-—eld thermal infrared imaging study of the star formation complex NGC 6334 in the southern Galactic plane. We imaged a 30@ region along the main star-forming ridge of NGC 6334 with pixel scale through broadband —lters for L (3.5 km) and 0A.6 M (4.8 km) and through narrowband —lters for the v \ 1¨0 Q-branch (2.42 km), polycyclic aromatic H 2 hydrocarbon (PAH) (3.3 km), and Bra (4.05 km) lines. The images reveal the spectacular, complex struc- ture of the photodissociation regions (PDRs) that pervade the region, with enhanced line emission around each of the seven sites of massive star formation along the ridge. Bubbles and loops of PAH emission, typically 1¨1.5 pc across, have been carved out of the parent molecular cloud by the intense UV radiation from the massive stars and surround H II regions (seen in Bra) typically 0.2¨0.3 pc across. The PAH emission regions coincide with both (C II) 158 km line emission, indicating that the PAHs are excited in PDR gas, and extensive emission, which therefore must be —uorescent. However, the tex- H 2 tures of the emission regions in PAH and are diUerent. This is attributable to variations in the physi- H 2 cal environment in which the gas is excited. Several compact reddened objects are observed; these are likely to be massive protostars. Subject headings: infrared: generalinfrared: ISM: lines and bandsISM: molecules ¨ ISM: structurestars: formationtelescopes