In the Footsteps of Apollo and the Shuttle, SpaceX's Falcon 9 Readies for Launch

Update: The SpaceX Falcon 9 launch was scrubbed Saturday morning and another attempt will be made on Sunday (Feb. 19) at 9:38 a.m. ET. The scrub in the final seconds of countdown will allow the company to "take a closer look at positioning of the second stage engine nozzle." Musk elaborated via Twitter: "All systems go, except the movement trace of an upper stage engine steering hydraulic piston was slightly odd. Standing down to investigate."

Original: With passenger spaceships in development and plans for settlements on Mars, Elon Musk's SpaceX has been uncharacteristically nostalgic this week as it prepares to launch its 30th Falcon 9 rocket.

The reason for the sentimentality is the rocket's launch pad, a historic site originally built in the 1960s to fly Americans to the moon. At the end of the Apollo program, the pad was refurbished for NASA's space shuttles, which flew for 30 years. The last launch from the pad was in July 2011.

Now, Launch Complex 39A, located at the Kennedy Space Center in Florida, is in the hands of SpaceX, which has spent millions preparing the site for its Falcon rocket fleet. The first Falcon launch from the pad is targeted for this weekend.

"I never get nervous speaking in front of a crowd and my heart is pounding to come out here today. Not because you guys make me nervous, but because I've got a vehicle on this extraordinary pad behind me," Gwynne Shotwell, president of SpaceX, told reporters at the launch pad on Friday.

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"It's a historic pad. We've taken good care of this pad during the refurbishment and the rebuild. We've saved precious things that needed to be saved. We've upgraded things to make them usable in the contemporary era here today. It's hard to express how excited I am to be here," Shotwell said.

"This pad would have just sat here and rusted away in the salt air had we not had the... agreement with SpaceX," added Kennedy Space Center director Bob Cabana, a former astronaut who flew four times on the space shuttle.

SpaceX in 2014 signed a 20-year lease on the pad, which will be used for Falcon 9 and planned Falcon Heavy rockets.

It has taken SpaceX almost three years to get 39A operational.

"There's nothing in particular that gave us a hard time. The whole thing is just a huge effort," said Hans Koenigsmann, SpaceX vice president of mission assurance.

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Putting the pad into service became a top priority after a September 2016 rocket explosion damaged what had been SpaceX's primary launch site just a few miles away. Repairs to that pad, located at Cape Canaveral Air Force Station just south of the NASA spaceport, are underway. Shotwell said the company is aiming to resume flights from Pad 40 this summer.

With a backlog of more than 70 missions, SpaceX wants multiple launch sites for operational flexibility. The company plans to use 39A for NASA missions, such as the cargo run to the International Space Station that is scheduled to blast off at 10:01 a.m. EST Saturday. In less than two years, SpaceX also plans to be flying crew to the station.

The other job for 39A will be to launch Falcon Heavy, with first flight slated for this year.

SpaceX also launches from Vandenberg Air Force Base in California, which is suitably positioned for polar and high-inclination orbits, and is building a fourth launch site in Texas.

Image: The SpaceX Falcon 9 and Dragon vehicle verticle at Pad 39A on Thursday night (SpaceX)