New Launch Date: May 30

Today, two veteran NASA astronauts, Robert Behnken and Douglas Hurley, boarded their Crew Dragon spacecraft, the Falcon 9 was fueled and readied for launch, spectators in the region and millions around the world eagerly waited the launch, the President and Vice President were in attendance. All eyes were on the rocket and the countdown clock. The countdown proceeded.

All systems were "go for launch," but the weather was doubtful. The ground crew waited until the very last minute, hoping that clouds and weather would clear.

But the weather didn't move out soon enough. Ground control jokingly asked "could you give us ten more minutes," but they knew that was impossible, and the historic launch of American astronauts flying on American rockets was 'scrubbed' until Saturday, May 30.

Safety is always number one, and launches are frequently delayed for weather or equipment issues. You want everything exactly right.

Some may be curious why the launch wasn't just delayed until the storm moved away. The simple answer is that for many launches, and especially for launches to a moving target like the International Space Station, the "launch window" can be only a few minutes wide or even "instantaneous," meaning that the launch must happen right at a specific moment. 

Had they launched just a few minutes later, the space station, orbiting at 17,000 miles per hour, would have traveled beyond the intended rendezvous point and required too much fuel to catch up to it once in orbit.

Our astronauts will reach the space station soon, and SpaceX and Boeing will before too long, begin taking tourists and scientists on commercial flights, whether to ISS or just to orbit, and one day, to commercial hotels and labs in orbit.