Update: The launch has been canceled for Thursday due to high winds and valve problems. NASA will try again Friday.
The Orion spacecraft is set to launch from Cape Canaveral.
Orion is aiming for two orbits on this inaugural run. On the second lap around the home planet, the spacecraft should reach a peak altitude of 3,600 miles, high enough to ensure a re-entry speed of 20,000 mph and an environment of 4,000 degrees. Splashdown will be in the Pacific off the Mexican Baja coast, where Navy ships already are waiting.
So far there have been five delays. The original scheduled launch time was 7:05 a.m. Thursday morning. You can follow the latest from NASA below.
The Associated Press contributed to this report.
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