I got to watch the launch of Magellan Venus probe aboard the Atlantis in 1989. We got VIP seats but it almost never happened. The countdown got to 31 seconds and the mission was scrubbed. There was only a narrow window of a couple of days to get the shuttle to launch Magellan or it would have to wait another 2 years for the right lauch angle to slingslot Magellan to Venus.They fixed the problem and launched within the open widow. It was one of the most amazing things I have ever witnessed.We flew home on a Sunday and the next day the shuttle we saw lauched at Cape Canaveral flew over our heads in SoCal and we saw the support jets and felt the sonic boom as it landed at Edwards AFB.
http://www2.jpl.nasa.gov/magellan/guide9.html