The overall reflectance of sunlight from Earth is a fundamental parameter for climate studies. We have designed and implemented small aperture, remote control telescopes in Big Bear Solar Observatory in California and in Tenerife in the Canary Islands. These telescopes observe the earthshine to obtain a global mean terrestrial reflectance utilizing

Context. The historic plates of the Carte du Ciel, an international cooperative project launched in 1887, offer valuable first-epoch material for the determination of absolute proper motions. Aims: We present the CdC-SF, an astrometric catalogue of positions and proper motions derived from the Carte du Ciel plates of the San Fernando zone

We present positions and magnitudes of stars and star clusters in a 1° × 1° area centered on M33. The survey is based on deep archival ground-based images using the MegaPrime camera on the 3.6m Canada-France-Hawaii telescope. We provide u′, g′, r′, i′, z′ magnitudes by performing standard profile-fitting photometry of these images and apply image

Assuming the standard cosmological model to be correct, the average linear size of the galaxies with the same luminosity is six times smaller at z = 3.2 than at z = 0; and their average angular size for a given luminosity is approximately proportional to z-1. Neither the hypothesis that galaxies which formed earlier have much higher densities nor

Nuclear rings are in most cases thought to be by-products of gas shock-focusing at Inner Lindblad Resonances (ILRs). AINUR (Atlas of Images of NUclear Rings) is an Atlas which includes images and metric measurements of all 109 known nuclear rings. This Atlas has been produced by checking and processing Hubble Space Telescope archive data from a

We present high-resolution spectroscopic measurements of the abundances of the α element titanium (Ti) and s-process elements yttrium (Y) and lanthanum (La) for 59 candidate M giant members of the Sagittarius (Sgr) dwarf spheroidal (dSph) + tidal tail system pre-selected on the basis of position and radial velocity (RV). As expected, the majority