Groans of disappointment were heard across Kennedy Space Center when the scrub discussion came down at 12:16 eastern time. Melissa Seuffert works with the Houston Symphony and had joined a select group of Twitterers at the launch site.
"We’re all disappointed, but of course, safety first. You want to make sure everything is good-to-go before you send those men up there, so…"
The problem surface soon after fueling. A thermostat didn’t turn on as expected in a heating unit. If it turns out the thermostat is broken, that could be an easy swap out. But if the problem is one of switches and detectors, then a fix could drag on. Right now, NASA is still aiming for a Monday afternoon launch. Robert Cabana is the Kennedy Space Center’s director:
"Well obviously, we would have very much loved to have see Endeavour lifting off this afternoon. That wasn't to be the case. I’d much rather be on the ground wishing I was flying, than in the air flying and wishing I was on the ground. Safety always comes first."
The heating units are critical because they keep hydraulic fluid from freezing when the shuttle goes into outer space. Without hydraulics, the mechanical systems of the shuttle could be in trouble. Clayton Anderson is an astronaut with two shuttle flights behind him.
"Anytime you activate your landing gear, or you steer your gimble, your engines, move your engines, those are the kinds of things that require hydraulics. So it’s pretty important we have those heaters working."
Hundreds and perhaps thousands of journalists and space enthusiasts must now decide whether to stick around until Monday, or beyond. Beth Schaefer drove from Houston to see the launch. After Monday, she’ll have nowhere to stay.
Launch Director Mike Leinbach describes the issue that scrubbed today's launch attempt.
"If it’s not Monday, I don’t know. I might be sleeping in my rented car (laughter)."
Schaefer, a Houston zookeeper, says she may decide to stick around. It’s a once-in-a-lifetime opportunity.
"Seeing the space shuttle is very inspirational. Just knowing that we’re sending people into space, which hardly anybody on the planet has gotten to do, is unbelievable. And if you believe in exploration and if you believe in the fact that we can’t just not find out what’s out there. You just want to be a tiny, tiny part of that, makes it worth all the crazy stress and insanity."
For now, the crew members will stay in Florida and wait for updates from the investigating engineers.