We report the discovery of burst oscillations at the spin frequency in ten thermonuclear bursts from the accreting millisecond X-ray pulsar (AMXP) IGR J17511-3057. The burst oscillation properties are, like those from the persistent AMXPs SAX J1808.4-3658 and XTE J1814-338, anomalous compared to burst oscillations from intermittent pulsars or non

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The nearby young σ Orionis cluster (˜360 pc, ˜3 Myr) is becoming one of the most important regions for the study of ultra low-mass star formation and its extension down to the mass regimes of the brown dwarfs and planetary-mass objects. Here, I introduce the σ Orionis cluster and present three studies that the {JOVIAN} group is developing: a pilot

We review here the multiplicity properties of ultracool dwarfs (spectral type later than M6) observed in three different environments and at three different ages: in the field, where the objects are relatively old (1-5 Gyrs) and isolated, in the Pleiades young (˜120 Myr) open cluster, and in the young (˜5 Myr) Upper Scorpius OB association (USco)

Widefield surveys have always provided a rich hunting ground for the coolest stars and brown dwarfs. The single epoch surveys at the beginning of this century greatly expanded the parameter space for ultracool dwarfs. Here we outline the science possible from new multi-epoch surveys which add extra depth and open the time domain to study.

We present and discuss the UV spectrum of the supergiant star in NGC206-277 in M 31, obtained with the Faint Object Spectrograph (FOS) on Hubble Space Telescope (HST). An optical blue spectrum taken at Kitt Peak National Observatory (KPNO) is also shown. From the optical and UV line spectra we classify the star B1.5Ia. We fit the continuum far-UV