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Radiative and dynamical energy exchanges in the planetary boundary layer are investigated by the simultaneous operation of a triaxial Doppler sodar, a zenith-pointing cryogenic radiometer with a bandpass centred around 850 μm wavelength, and additional meteorological equipment for near-ground reference. The two instruments provide measurements of the wind field and of the atmospheric radiative temperature, respectively. Two measurement campaigns were carried out in the Rome area in the periods 12–18 Sept. 1990 and 16–22 Sept. 1991. Data were analysed for correlation and used to calculate kinematic eddy sensible heat fluxes. Depending on the meteorological conditions, high values of correlation were found between the fluctuations of the height-averaged (300 m) vertical wind speed and the radiative temperature, in the presence of clear-sky convection. The highest values of correlation were obtained for delays of a few minutes, as expected in agreement with typical dimensions of convective structures in the boundary layer. Estimates of the kinematic eddy sensible heat flux gave average values as high as 0.14 K m s−1 in daytime and 0.005 K m s−1 at night.

The need for accurate and complete maps of the galaxy at radio frequencies is made evident not only by the importance of the data in the study of galactic dynamics and structure formation but also in the analysis of cosmic background radiation data. A summary of the existing radio surveys of our galaxy is presented along with their limitations. A new program, the Galactic Emission Mapping (GEM) project, to obtain calibrated and complete maps of the galaxy in the 400 to 1400 MHz range, is outlined.

During the Italian Antarctic Expedition 2004/2005 we observed Mercury at 150 and 240 GHz. The observations have been carried out by means of the 2.6 m OASI telescope. By using the responsivity of our detectors, obtained from Venus, the brightness temperature of the planet was derived.

OASI (Infrared and Sub-mm Antarctic Observatory) is the first large telescope permanently installed in Antarctica. It is located close to the Italian Base in Antarctica (Terra Nova Bay Station, latitude: 74.39 S, longitude: 164.09 E). The OASI first light was received in December 1990 when the wobbling secondary mirror was mounted. The telescope is planned to be an open facility which can operate in the wavelengths range between 350 μm and 3mm. The sky coverage from OASI goes down to a declination of about-35° for a 24 hours/day observing time.

We show how combined large-beam infra-red and radio observations toward the Virgo Cluster may be explained by assuming the existence of a large tepid halo surrounding the giant galaxy M87. Such a halo would be able to close the cluster gravitationally. If interpreted as being due to bremmstrahlung radiation by a tepid extended halo, it also explains the infra-red observations, and it has important implications for the physics of M87.

The possibility of detecting diffuse sky radiation in the (250÷3000) μm range is discussed on the basis of recent measurements performed at the mountain observatory of Testa Grigia (3500 m a.s.l.) on the atmospheric emission and on the atmospheric noise. It is shown how, in many cases, the limits assigned by the residual atmospheric emission are well below the sensitivity of the available infra-red detectors; as a consequence some new experiments of background astronomy are suggested.

We present the results of a balloon flight devoted to the observation of the diffuse sky radiation in the wave-length region (150÷400) and (350÷3000) μm, at angular scales larger than six degrees. Observations of dust emission and distribution are discussed.