Based on the most widely accepted model for structure formation in the Universe, the massive galaxies we see today are the result of the merging of smaller structures. Looking far enough, and therefore far back in time, one should then be able to see galaxies getting smaller and smaller. To explore this issue we focus on quasars host galaxies and

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Follow-up RXTE PCA observations of the transient source consistent with the position of SAX J1808.4-3658 (ATEL#505) showed clear coherent pulsations at approximately 401 Hz. This frequency is identical to the spin frequency of the neutron star in SAX J1808.4-3658 demonstrating that it is indeed SAX J1808.4-3658 which is in outburst again. During

We have discovered 13 new candidate Planetary Nebulae (PNe) in the dwarf irregular galaxy NGC 6822, increasing its total number to 17 objects. Our sample of candidate PNe is complete down to 3.5 mag below the brightest PN.

We report optical photometry and spectroscopy of the candidate optical/NIR counterpart (ATEL #526, #533) to the millisecond X-ray pulsar HETE J1900.1-2455 (ATEL #516, #523, #538). Its consistency with the recent SWIFT localisation (ATEL #541) and our ground-based observations confirm its association with the X-ray source. Photometry was acquired

We present the first determination of the proper motion of the neutron star low mass X-ray binary Cen X-4 measured from relative astrometry of the secondary star using optical images at different epochs. We determine the Galactic space velocity components of the system and find them to be significantly different from the mean values that