Space Cadets! Launch your bones from bed before 6 a.m. tomorrow. A feast awaits. At 5:50 a.m. (standard time) the International Space Station and maybe shuttle Discovery will rise in the southwest, passing the bright star Sirius. They'll climb more than halfway up the southeastern sky, brushing Saturn at 5:53 a.m. before zipping off to the northeast. Mars gleams, reddish, just west of straight up. Look east. The crescent moon stands beside brilliant Venus. Elusive Mercury shines below them, to the left.