WISE Launch Slips to Saturday
Note: As palmerin mentions below, the launch is now scheduled for Monday. Enjoy the free weekend! I bet the mission team is frustrated!
The WISE launch, originally scheduled for yesterday, has slipped to Saturday morning. The current WISE mission launch page indicates that the reason for the slip is a “problem with a booster steering engine.” Such a problem could range from relatively minor (two sensors giving incompatible readings) to serious (some hardware failure could make the booster unsteerable). But with a 24 hour hold, it’s probably a minor issue.
When your launch window is less than 14 minutes (6:09:33 – 6:23:51 a.m. PST for Saturday), you only get one shot at launching. The typical Delta-II recycle time (how long it takes to get a second try) is about 20 minutes. I’ve seen it done in 17 minutes, and that was very fast. If the problem requires more than a few moments to figure out, the launch is usually scrubbed (postponed) and rescheduled for a later time. How long they wait depends on the severity of the problem. The minimum time is however long it takes to get to the next launch window that will put the spacecraft into the proper orbit. For a mission like WISE, that time is probably 24 hours, hence the 24-hour delay.
Sadly, that means those of us who are launch junkies have to actually drag ourselves out of bed on Saturday morning if we want to watch the launch. But hey, at least we aren’t gonna have to work the weekend!