CHALLITA , Z.

Context. The winter seeing at Concordia is bimodal, i.e. either excellent or quite poor, depending on the altitude above the snow surface. We study the temporal behavior of the good seeing sequences. Efficient exploitation of extremely good seeing conditions with an adaptive optics system requires long integrations.Aims: We examine the temporal...

The optical turbulence above Dome C in winter is mainly concentrated in the first tens of meters above the ground. The properties of this so-called surface layer were investigated during the last two winterover by a set of sonics anemometers placed on a 45 m high tower. These anemometers provide measurements of the temperature and the wind...

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We present long term site testing statistics based on DIMM and GSM data obtained at Dome C, Antarctica. These data have been collected on the bright star Canopus since the end of 2003. We give values of the integrated turbulence parameters in the visible (wavelength 500 nm). The median value we obtained for the seeing are 1.2 arcsec, 2.0 arcsec...

So as to prepare future observations of terrestrial extrasolar planets liable to shelter life, we attempt to detect the life on the Earth seen as a dot. We use the Moon Earthshine, in which any place reflects the totality of the enlightened part of Earth facing the Moon. Observing from OHP and from ESO, we detected terrestrial chlorophyll in...

The optical turbulence above Dome C in winter is mainly concentrated in the first tens of metres above the ground. Properties of this so-called surface layer (SL) were investigated during the period 2007–2012 by a set of sonic anemometers placed on a 45 m high tower. We present the results of this long-term monitoring of the refractive index...

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Astronomy and Astrophysics, 511, p. 36 (2009)

Aims. Over the past few years a major effort has been put into the exploration of potential sites for the deployment of submillimetre astronomical facilities. Amongst the most important sites are Dome C and Dome A on the Antarctic Plateau, and the Chajnantor area in Chile. In this context, we report on measurements of the sky opacity at 200 μm...

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