Word out of Vandenberg Air Force Base is that an Atlas 5 rocket is scheduled for launch at 8:29 p.m., and with anticipated clear skies tonight its trajectory into orbit to deliver its classified payload should be visible to the unaided eye within a radius of 150 miles.

“The 19-story rocket should be visible across the region as a flame in the night sky, streaking southward to orbit,” reports Justin Ray at the launch’s Mission Status Center page on the Spaceflight Now website.

Because I’m known to geek out about witnessing things like that, and have a decent view of the western skies from up on our roof, you might just find me up there around that time hoping the launch goes off as planned and trying to record the event — not to be confused with “The Event” on TV, which I will neither be recording nor watching.

UPDATED (9:33 p.m.):

Delayed until 9:03 p.m. (because of a reported vehicle parked within the unsafe zone of the launch pad, but I think it was because the Saints/49ers Monday Night Football got really exciting at the end), the launch was a complete success on Vandenberg’s end, but a total bust on mine. Too much of an onshore-flowing marine layer obscured any opportunity to see the Atlas fly. Fact is, even on a crystal clear night it wouldn’t have been all that dramatic. The launch vehicle may be almost 200 feet tall, but from my rooftop about 150 miles away fromliftoff it probably wouldn’t have been more than a scratch of light across the night sky.