A unit of measurement of time in Vernor Vinge's A Deepness in the Sky. It corresponds to about 11 1/2 days (ok, to be exact: 11 days, 13 hours, 46 minutes and 40 seconds). It is a measure of time used in space, because in the time the book is set, Earth has entered into legend and is no longer of any significance, nor do days months or years. So time is measured, even in common conversations, as kiloseconds and megaseconds.