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This Letter presents an analysis of three-dimensional vector currents and temperatures observed in a sunspot from the photosphere to the chromosphere, spanning a range of heights of approximately 1500 km. With this unique data set, based on novel spectropolarimetric observations of the 850 nm spectral region, it is possible to conduct for the first

We present 16600 equivalent widths (EWs) in the spectra of 100 and 94 stars with and without known planets, respectively. We have measured line-by-line EWs of about 80 spectral lines for the refractory elements Si, Ca, Sc, Ti, V, Cr, Mn, Co, Ni. The EWs of about 14 lines of Na, Mg and Al in 53 new comparison spectra have been added to the previous

We present our observations of several planetary nebulae in the central zones of the spiral galaxy M33. We combine the abundances we derived for our objects with those obtained by Magrini et al. (2004) for a sample of PNe at larger galactocentric distances. We compare the radial abundance distribution derived from planetary nebulae with the one

Traditionally the Earth's reflectance has been assumed to be roughly constant, but large decadal variability, not reproduced by current climate models, has been reported lately from a variety of sources. We compare here the available data sets related to Earth's reflectance, in order to assess the observational constraints on the models. We find a