16th of June 2015 . ASKAP HI imaging of the galaxy group IC 1459 . ... One of these observations was aimed at studying the distribution of neutral hydrogen (HI) gas in the galaxy group IC 1459. ... HI found outside galaxies in this group amounts to at least 10% of the HI contained inside galaxies. This suggests a substantial flow of gas in and out of galaxies during the several billion years of the group's evolution. ... today * ATNF | ... ASKAP | ...

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