NASA has abandoned its attempt to launch the shuttle Endeavour today after another hydrogen leak.

A 13 June launch attempt was called off for the same reason.

“We’re going to step back and figure out what the problem is and go fix it,” says Space Shuttle Program Manager LeRoy Cain. “Once we get it fixed and we’re confident that we have a solution that’s going to work and allow us to go fly safely, then we’ll proceed forward.”

At the moment the next launch attempt is scheduled for 11 July. All eyes are now on the Lunar Reconnaissance Orbiter which is being wheeled out today for a launch tomorrow atop an Atlas V rocket.

On his twitter feed, Endeavour mission commander Mark Polansky says, “I’m sure you all know that we postponed again. It’s a reminder that spaceflight is NOT routine. We will fly home to Houston this morning.”

Image: the Ground Umbilical Carrier Panel area on space shuttle Endeavour’s external fuel tank, site of the hydrogen leaks / NASA TV