Snodar: 2009 performance at Dome A, Antarctica

Dome A on the Antarctic plateau is likely one of the best observing sites on Earth thanks to the excellent atmospheric conditions present at the site during the long polar winter night. We present high-cadence time-series aperture photometry of 10,000 stars with i < 14.5 mag located in a 23 deg 2 region centered on the south celestial pole. The photometry was obtained with one of the CSTAR telescopes during 128 days of the 2008 Antarctic winter. We used this photometric data set to derive site statistics for Dome A and to search for variable stars. Thanks to the nearly uninterrupted synoptic coverage, we found six times as many variables as previous surveys with similar magnitude limits. We detected 157 variable stars, of which 55% were unclassified, 27% were likely binaries, and 17% were likely pulsating stars. The latter category includes δ Scuti, γ Doradus, and RR Lyrae variables. One variable may be a transiting exoplanet.

show abstract

“…This was confirmed by Snodar measurements in 2009. The median thickness of the boundary layer was 14m (Bonner et al 2010).…”

Section: Introductionmentioning

confidence: 99%

Photometry of Variable Stars From Dome A, Antarctica

Wang

Macri

Krisciunas

et al. 2011

The Astronomical Journal

Self Cite

View full text Add to dashboard Cite

show abstract

“…Competition between shear and buoyancy weakens turbulence and results in a shallower boundary layer. We list the monthly median boundary layer heights of Dome A in 2009 (Bonner et al 2010) and the monthly median temperature difference at 4 m during 2011 in Table 3 and compared them in Fig. 22.…”

Section: Conclusion and Discussionmentioning

confidence: 99%

Meteorological Data for the Astronomical Site at Dome A, Antarctica

Hu¹,

Shang²,

Ashley³

et al. 2014

Publications of the Astronomical Society of the Pacific

Self Cite

View full text Add to dashboard Cite

We present an analysis of the meteorological data collected at Dome A, Antarctica by the Kunlun Automated Weather Station, including temperatures and wind speeds at eight elevations above the snow surface between 0 m and 14.5 m. The average temperatures at 2 m and 14.5 m are −54 • C and −46 • C, respectively. We find that a strong temperature inversion existed at all heights for more than 70% of the time, and the temperature inversion typically lasts longer than 25 hours, indicating an extremely stable atmosphere. The temperature gradient is larger at lower elevations than higher elevations. The average wind speed was 1.5 m/s at 4 m elevation. We find that the temperature inversion is stronger when the wind speed is lower and the temperature gradient decreases sharply at a specific wind speed for each elevation. The strong temperature inversion and low wind speed results in a shallow and stable boundary layer with weak atmospheric turbulence above it, suggesting that Dome A should be an excellent site for astronomical observations. All the data from the weather station are available for download.

show abstract

“…Above this height, a telescope would be in the free-atmosphere for half the time. From Bonner et al (2010).…”

Section: Astronomical Seeing and Atmospheric Turbulencementioning

confidence: 99%

“…The most definitive measurements of the height of the boundary layer on the Antarctic plateau have been made by the Snodar instrument at Dome A (Bonner et al 2010, see Figure 2). Snodar is a sonic radar that was purpose built to probe turbulence close to the ice with 1 m resolution (Bonner et al 2009).…”

Section: Astronomical Seeing and Atmospheric Turbulencementioning

confidence: 99%