Today, the knowledge of the solar radiative interior is obtained by the solar acoustic modes. Thanks to the latest modes detected by SoHO the sound speed has been determined down to 0.06 Ro with a resolution of 3%. This profile is used to improve the solar model and its deviations from a static vision. The rotation profile is now clearly

Using a radically new suite of data extraction routines, IUEARM, high resolution IUE spectra of six F and G stars, taken at regular intervals since 1978 are analysed. The salient features of the new routines are: reduction of interorder scattering via two-dimensional deconvolution of the echelle spectrograph image plane, with high frequency

The Spitzer Survey of Stellar Structure in Galaxies ( 4G ) is an Exploration Science Legacy Program approved for the Spitzer post-cryogenic mission. It is a volume-, magnitude-, and size-limited ( d 40 Mpc , | b | > 30 ° , mBcorr 15.5 , and D25 > 1') survey of 2331 galaxies using the Infrared Array Camera (IRAC) at 3.6 and 4.5 μm. Each galaxy is

We propose the ultimate survey of the distribution of stellar structure in the nearby universe using IRAC's 3.6 and 4.5 micron channels. Deep observations of the stellar mass distribution, down to 0.1 Msun per sq. pc for a sample of ~2,300 nearby (d

We present results from an investigation of the peculiar "Tadpole Galaxy" (UGC 10214) using mid-infrared imaging from the Spitzer Wide-area Infrared Extragalactic Survey (SWIRE) observations of the ELAIS N1 region, which includes UGC10214 and its local environment. The Spitzer imaging data comprise the four mid-infrared channels of IRAC and the 24

We present results on the star formation history of the Local Group dSph galaxy Leo I, obtained through the analysis of its deep HST color-magnitude diagram (CMD) using model CMDs computed from stellar evolutionary models. Our results show unambiguously that Leo I experienced a major increase of its star formation rate from about 6 Gyr ago to 2 Gyr