NASA will try again to launch the space shuttle Endeavour on June 17, and still push to get the Lunar Reconnaissance Orbiter (LRO) under way this week as well.
Both spacecraft were scheduled to launch from Florida that day, after a gaseous hydrogen leak forced the shuttle program to scrub Endeavour's planned June 13 launch. But in an effort to "maximize" the space agency's launch opportunities this week, the LRO team relinquished its June 17 slot to the space shuttle program to give Endeavour one more chance to lift off to the International Space Station (ISS) before its launch window closes until July.
The glitch with the shuttle is not a big issue, since things as complicated as aircraft (or in this case, a spacecraft) always have problems. The big issue, however, is that NASA is apparently unable to launch the rocket with the probes while the shuttle is still sitting on the pad. The official NASA press release on the matter, doesn't mention the reason why this is the case.
There are a couple of reasons why this might be, but they are immaterial. The fact that NASA can't send the probes up with a shuttle on the pad, is inexcusable. If this nation is going to be serious about space, then it must be able to launch a vehicle, manned or unmanned, at any time, with no delays or hitches because there's something else waiting to go up. Costs for spaceflight will only go down as they become more commonplace, and that can't happen if NASA's facilities are tied up because something on another launch pad is having problems.
As I write this, NASA is twittering that weather conditions are making it impossible to fuel the shuttle. If the shuttle doesn't get fueled by a certain point, then they can't do the launch of the shuttle, and its mission to the ISS will have to wait, so that the lunar probes can be launched. Again, not at all what we want in a spacefaring nation.
UPDATE: NASA is now saying that they're fueling Endeavour's tanks.