SAX J1747.0-2853 is an X-ray transient which exhibited several outbursts between 1998 and 2001 and most probably in 1976. The outburst of 2000 was the longest and brightest. We have analyzed X-ray data sets that focus on times around the 2000 outburst and were obtained with l BeppoSAX, XMM-Newton and l RXTE.

Asteroids in cometary orbits can be defined as minor planets that do not present cometary activity and has orbits with Tisserand parameter T 3 (typical of cometary orbits). The nature and origin of this population is still controversial. Recent dynamical studies claim for a cometary origin (comets that become dormant or dead comets by the growth

Based on a new large, homogeneous photometric database of 69 Galactic globular clusters extended out to 42 kpc from the galactic center, a set of distance and reddening free relative age indicators has been measured: delta (V-I)@2.5 and Delta VHBTO. Using this two independent indicators and two recent updated libraries of isochrones we have found

We report on a novel investigation of the complex magnetism of the quiet Sun which is based on a realistic three-dimensional modeling of the Hanle effect.

HETE-2 (High Energy Transient Explorer) is a small scientific satellite whose main task is to detect Gamma-Ray Bursts, promptly determine their coordinates, when possible, and distribute them immediately to the scientific community. HETE-2 has detected many of the most interesting events in recent years: GRB030329, which confirmed beyond any doubt

RX J1211+2242 is an optically faint (B ≃ 19.2 mag) but X-ray bright (f2 - 10 keV = 5 × 10-12 erg cm-2 s-1) AGN, which has been shown to be a BL Lac object at redshift z = 0.455. The ROSAT X-ray, Calar Alto optical, and NVSS radio data suggest that the peak of the synchrotron emission of this object is at energies as high as several keV. BeppoSAX