Update: SpaceX plans to launch Intelsat 35e today (July 5) at 7:37 p.m. EDT (2337 GMT). You can watch the liftoff live here on Space.com, courtesy of SpaceX.
For the second day in a row, SpaceX scrubbed the launch of a communications satellite with just 10 seconds left on the countdown clock.
A SpaceX Falcon 9 rocket was scheduled to lift off at 8:35 p.m. EDT Monday (July 3; 0035 GMT on July 4) from Pad 39A at NASA's Kennedy Space Center in Florida, and carry the 13,000-lb. (6,000 kilograms) Intelsat 35e satellite to orbit.
But controllers called off the liftoff with just 10 seconds to go — just as they did on Sunday (July 2), Intelsat 35e's original launch date.
Sunday's abort was triggered by a potential issue with the Falcon 9's guidance system and/or the hardware that supports it, SpaceX representatives said. It was not immediately clear what the cause was on Monday, Falcon 9 principal integration engineer John Insprucker said during SpaceX's launch webcast.
"Standing down today due to a violation of abort criteria, vehicle/payload in good health, next launch opportunity tomorrow, July 4th!" SpaceX representatives said via Twitter on Monday evening.
Intelsat 35e is ultimately headed for geostationary orbit, about 22,300 miles (35,800 kilometers) above Earth. The satellite's weight and faraway destination mean that the Falcon 9 first stage will not attempt a landing after liftoff; it won't have enough fuel left over to steer its way back down for a soft landing, Insprucker said.
Monday's launch was supposed to take place at 7:37 p.m. EDT (2337 GMT), but SpaceX pushed the attempt back to 8:35 p.m. EDT — the very end of the window — to give bad weather a chance to clear.