U.S. aerospace firm SpaceX stood down on the launch of Zuma spacecraft scheduled for Thursday to review "data from recent fairing testing for another customer", pushing the mysterious launch to Friday at the earliest.
"Though we've preserved the range opportunity for tomorrow, we'll take the time needed to complete the data review and then confirm a new launch date," the company tweeted on Thursday.
SpaceX, based in the state of California, is now targeting the launch of Zuma spacecraft atop a SpaceX Falcon 9 rocket on Friday from Launch Complex 39A (LC-39A) at the U.S. National Aeronautics and Space Administration (NASA)'s Kennedy Space Center in Florida.
This will be Falcon 9's 17th flight in 2017. The Falcon 9 rocket is set to deliver perhaps its most secretive payload yet, a classified government satellite built by defense contractor Northrop Grumman, to low-Earth orbit.
The purpose of the mission, codenamed Zuma, is essentially unknown. It's unclear what kind of spacecraft is going up, or which government agency the launch is for.
The launch comes just one month after the mission became public, when media reported on documents that SpaceX had filed with the U.S. Federal Communications Commission, requesting authorization for a launch license as Mission 1390. As reported, Zuma is a commercially contracted, built, and operated clandestine spacecraft by Northrop Grumman via a contract award from the U.S. government.
Following stage separation, Falcon 9's first stage will attempt to land at the company's Landing Zone 1 at Cape Canaveral Air Force Station in Florida, SpaceX said.
To date, SpaceX has returned and landed a Falcon 9's first stage 19 times on land and at sea. Such landings are part of SpaceX's efforts to develop fully reusable rockets, which the company believes could bring down spaceflight costs. It stands to reason that the selection of the Falcon 9 was by far the cheapest and most launch-date reactive choice for Zuma.
This is actually not the first time SpaceX has sent something secret into space. After receiving certification in 2015 to launch military satellites, the company has already launched two classified payloads this year, and is slated to launch more over the next couple of years.
In May, a Falcon 9 rocket delivered the NROL-76 spy satellite for the National Reconnaissance Office, and followed that with the launch of an uncrewed X-37B space plane on Sept. 7 on the OTV-5 mission for the U.S. Air Force.
Earlier this month, SpaceX suffered a rocket-engine explosion during a test of its next-generation model at the company's test facility in the city of McGregor, Texas, when a propellant leak ignited, damaging the test stand, according to media reports.
The setback came the company conducted 16 successful missions in 2017, twice as many as its previous high in a calendar year. Also, SpaceX has landed this year 13 of those rockets back on Earth after launch.
SpaceX is still investigating the McGregor explosion to find its "root cause." Despite the explosion, the spaceflight company will push on with its planned launches uninterrupted.
This is not the first time SpaceX has experience failure investigation. On Sept. 1, 2016, a Falcon 9 blew up on the launch pad during a routine preflight test, destroying the rocket, its payload and the launch pad, but no one was hurt.
In 2015, SpaceX's Falcon 9 rocket exploded a couple of minutes after lifting off from Cape Canaveral en route to deliver cargo to the International Space Station. No one was on board nor injured.