... Programme . ... Abstract: As the nearest early-type galaxy, Centaurus A contains a treasure trove of information about X-ray binaries. With over 700 ks of Chandra observations spread over 10 years, the Centaurus A Very Large Project provides the deepest look at X-ray binaries in an early-type galaxy. ... Preliminary results have already shed light on the low-mass X-ray binary connection to globular clusters and the discovery of a remarkable transient ultra-luminous X-ray source. ...

metrologia The leap second: its history and possible future R. A. Nelson, D. D. McCarthy , S. Malys, J. Levine, B. Guinot, H. F. Fliegel , R. L. Beard and T. R. Bartholome w Abstract. This paper reviews the theoretica l motivatio n for the leap second in the context of the historica l evolutio n of time measurement . Th e periodic insertio n of a leap second step into th e scale of Coordinate d Universal Time (UTC) necessitates frequent changes in comple x timekeepin g systems an d is currentl y th e