We obtained deep imaging and high-resolution spectroscopy of the planetary nebula NGC 2438. In addition to the bright inner rim and the faint halo-like shell already known from previous imagery, our observations also highlight the existence of an even fainter large halo of nearly spherical shape. Analysis of the surface-brightness profiles and the

We report new Hubble Space Telescope WFPC2 and NICMOS observations of the center of the nearest radio galaxy Centaurus A (NGC 5128) and discuss their implications for our understanding of the active nucleus and jet. We detect the active nucleus in the near-IR (K and H) and, for the first time, in the optical (I and V), deriving the spectral energy

The results of the Tenerife cosmic microwave background (CMB) experiments are presented. These observations cover 5000 and 6500 deg2 on the sky at 10 and 15 GHz, respectively, centered on decl.~+35deg. The experiments are sensitive to multipoles l=10-30 that correspond to the Sachs-Wolfe plateau of the CMB power spectra. The sensitivity values of

We describe the ROSAT International X-ray/Optical Survey (RIXOS), a medium-sensitivity survey and optical identification of X-ray sources discovered in ROSAT high Galactic latitude fields (|b|>28 deg) and observed with the Position Sensitive Proportional Counter (PSPC) detector. The survey made use of the central 17arcmin of each ROSAT field. A

We present morphological and photometric properties of 79 low redshift (z=-24.0 with a clear trend for FRI sources to be ~ 0.5 mag brighter than FRII galaxies. In about 40% of the objects observed we find an excess of light in the nucleus that is attributed to the presence of a nuclear point source whose luminosity is on average ~ 1-2% of the total

The luminosity function of the globular cluster Palomar 1 is determined together with its confidence interval by applying an adaptive kernel estimator to data from the Isaac Newton Telescope. The luminosity function of Palomar 1 has two minima in the V band and one in the I band. The cluster core contains a relatively high fraction of bright stars