In order to test the expansion of the universe and its geometry, we carry out an Alcock-Paczyński cosmological test, that is, an evaluation of the ratio of...

Some remarkable examples of alternative cosmological theories are reviewed here, ranging from a compilation of variations on the Standard Model through the more...

The existence of life is one of the most fundamental problems of astrophysics. The intriguing existence of progressively complex and apparently improbable...

We show herein that a proto-cluster of Ly α emitting galaxies, spectroscopically confirmed at redshift 6.5, produces a remarkable number of ionizing continuum...

An IUE archive spectrum of HD 140283 has been analyzed in the region of the 3131 Å 9Be II resonance doublet. Close comparison of the observed and synthetic...

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...

How the cosmic web feeds haloes, and fuels galaxy formation is an open question with wide implications. This study explores the mass assembly in the Local Group...

An observing campaign with 10 participating observatories has undertaken to monitor the optical brightness of the Q0957 gravitationally lensed quasar for 10...

We report on an observing campaign in 2001 March to monitor the brightness of the later arriving Q0957+561B image in order to compare with the previously...