We present new results on the Hubble diagram of distant type Ia supernovae (SNeIa) segregated according to the type of host galaxy. This makes it possible to check earlier evidence for a cosmological constant by explicitly comparing SNe residing in galaxies likely to contain negligible dust with the larger sample. The cosmological parameters

The proto-planetary nebula Hen 3-1475 shows a remarkable highly collimated optical jet with an S-shaped string of three pairs of knots and extremely high velocities. We present here a detailed analysis of the overall morphology, kinematic structure and the excitation conditions of these knots based on deep ground-based high dispersion spectroscopy

The surface brightness profile in the V band of the Phoenix dwarf galaxy shows two stellar components: an inner one, which contains all the young stars of the galaxy, and an outer one predominantly populated by red stars. Deep color-magnitude diagrams (CMDs), based on Hubble Space Telescope (HST) observations and reaching the oldest turn-offs, are

We investigate the evolution of mass-selected early-type field galaxies using a sample of 28 gravitational lenses spanning the redshift range 0

We report 323 hours of nearly uninterrupted time series photometric observations of the DBV star GD 358 acquired with the Whole Earth Telescope (WET) during May 23rd to June 8th, 2000. We acquired more than 232,000 independent measurements. We also report on 48 hours of time-series photometric observations in Aug 1996. We detected the non-radial g

Since 1998 the Earthshine Project has been a collaborative effort between Big Bear Solar Observatory/New Jersey Institute of Technology and the California Institute of Technology. Cyclic spectroscopic observations of the dark and bright sides of the moon (or earthshine and moonshine respectively) have been carried out in the visible range at