Plenty of clouds remained Sunday when SpaceX's Falcon 9 rocket launched. Trevor Mahlmann This was the fourth flight of this first stage. Trevor Mahlmann The first stage made a successful return to a landing site near the launch pad. Trevor Mahlmann
As a strengthening low pressure system crossed the Florida peninsula on Sunday, weather conditions at Cape Canaveral Air Force Station were poor all day. There were intermittent showers and plenty of lightning.
By mid-morning, SpaceX had already canceled one launch from Florida, a mission carrying five dozen Starlink satellites. But the company held out hope for getting the second flight of a planned doubleheader off on Sunday evening, and by the time the clock ticked down on the SAOCOM-1B mission, weather conditions began to marginally improve.
At 7:18 pm ET (23:18 UTC) launch-site weather had only just turned green, so a thrice-used Falcon 9 first stage took off on its fourth flight. And a historic one it was as SpaceX launched a rocket for the 100th time, and flew a rare polar corridor mission from Florida for Argentina's space agency.
The century mark
SpaceX launched its first rocket in March, 2006. This was the small Falcon 1 rocket, which failed about half a minute into flight after its single Merlin engine caught on fire. After two more failed attempts SpaceX would reach orbit on September 28, 2008, with the Falcon 1 rocket.
The company then turned its attention toward developing the larger Falcon 9 rocket, which flew in 2010 for the first time. SpaceX launched its 10th overall mission in March, 2013.
Since then there has been an acceleration in launch cadence has SpaceX has developed five versions of its Falcon 9 rocket and the Falcon Heavy booster. The company required seven years to go from its first to its tenth launch. In seven more years SpaceX has gone from itRead More – Source
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