CAPE CANAVERAL, Fla. -- They supported some of the nation’s first satellite launches, helped send probes to other planets and established the GPS satellite constellation so embedded in everyday life.

But in an instant Thursday morning, the twin towers at Launch Complex 17 collapsed in a cloud of dust, brought down by controlled explosions as about 100 spectators looked on a short distance away.

Brig. Gen. Wayne Monteith, commander of the Air Force’s 45th Space Wing, presided over a brief demolition ceremony that closed a storied chapter in Cape history, while opening another that could see the private sector take a lead role in exploration.

Launch Complex 17B cape canaveral
NASA's THEMIS spacecraft atop a Delta II rocket stood on Launch Complex 17B at Cape Canaveral Air Force Station before launch on Feb. 17, 2007. The complex's two pads are largely identical and both hosted historic missions.
NASA/George Shelton

“Keep your fingers crossed that I won’t mess this up,” Monteith joked before initiating the charges just after 7 a.m. “We are getting ready to leap into the future.”

With a warning siren, a final 3-2-1 countdown and cry of “fire in the hole!”, explosives flashed with loud bangs near the bases of pads 17A and 17B, sending them toppling sideways in opposite directions.

Complex 17 was activated in 1957 for test launches of Thor ballistic missile, and later was known for space missions by Delta rockets. In all, it hosted 325 launches.

Most recently the site was home for more than 20 years to United Launch Alliance’s workhorse Delta II program, which last flew from the Cape nearly seven years ago, sending a pair of pair of gravity mapping probes to the moon for NASA on Sept. 10, 2011.

The $2 million demolition project had been in the works since then.

Delta II rockets launched multiple orbiters and landers to Mars, including the Spirit and Opportunity rovers in 2003. Opportunity remains active today.

The Delta II program launched nearly 50 Global Positioning System satellites from Florida for the Air Force, helping to establish a precise navigation and timing system that transformed military operations and which ordinary citizens rely upon daily for everything from driving directions to financial transactions.

One more Delta II launch remains, planned this September from California.

Launch Complex 17 and neighboring Complex 18 now are occupied by Moon Express, a private company developing small lunar landers that NASA may use to send science instruments to the lunar surface in the next few years.

Moon Express is testing engines and landers at the site, but they will be launched atop rockets from other pads or possibly other launch sites.

Launch Complex 17 had been Cape Canaveral’s southernmost launch site, offering spectators close-up views from Port Canaveral and Jetty Park just a few miles to the south.

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