* Astronomy

According to Larry Williams, SpaceX's vice president the countdown was held at the T-minus-10-minute mark due to weather concerns. This was followed by another delay when technicians had to fix a venting problem in the liquid-oxygen tanks at the launch pad.
So much liquid oxygen and helium had been vented, that the supply will have to be replenished from Hawaii, more than 3,200 kilometres to the northeast.

"It's a minimum delay of one to two weeks" - spokeswoman for Space Exploration Technologies Corporation.

"What happened was that an auxiliary liquid oxygen (LOX) fill tank had a manual vent valve incorrectly set to vent. The time it took to correct the problem resulted in significant LOX boil-off and loss of helium, and it was the latter that caused the launch abort. LOX is used to chill the helium bottles, so we lose helium if there is no LOX to cool the bottles. Although we were eventually able to refill the vehicle LOX tanks, the rate at which we could add helium was slower than the rate at which LOX was boiling away. There was no way to close the gap, so the launch had to be called off. In addition, we experienced an anomaly with the main engine computer that requires further investigation and was arguably reason in and of itself to postpone launch" - Elon Musk, chief executive officer.