The loss of the secretive Zuma satellite — which was launched by SpaceX in January — was reportedly due to a problem with a part modified by Northrop Grumman Corp. that attaches the payload to the rocket.
Two separate teams of government and industry investigators have "tentatively concluded" that the piece of hardware, known as a payload adapter, failed to properly operate in space due to "engineering and testing errors by Northrop Grumman," according to a report late Sunday by the Wall Street Journal.
Citing a "person familiar with the process," the Journal reported that the payload adapter was bought from a subcontractor but "significantly modified" and tested three times by Northrop Grumman, which also built the Zuma satellite for the U.S. government.
When the part reached orbit, it didn't detach the satellite from the Falcon 9 rocket, as expected. Instead, the satellite fell back into the atmosphere with the rocket's returning second stage; it eventually broke free, but had "dropped to an altitude that was too low for a rescue," according to the Journal.
Northrop Grumman and SpaceX did not respond to requests for comment.
Little was known about the Zuma mission, the purpose of the satellite or even the aftermath of the launch. SpaceX launched the classified satellite from Cape Canaveral Air Force Station in Florida, but as with all national security launches, the Hawthorne space company — which is led by Elon Musk and whose full name is Space Exploration Technologies Inc. — ended its live stream shortly after the first and second stages of the rocket separated.
However, the company had said during the livestream that it had gotten confirmation that the fairing — the clamshell-like covering that protects payloads at the tip of the rocket — had deployed.
The next day, reports trickled in that the satellite, code-named Zuma, may have been lost. SpaceX vigorously defended the performance of its rocket, and company President Gwynne Shotwell said in a statement at the time that "after review of all data to date, Falcon 9 did everything correctly" during the launch.
"If we or others find otherwise based on further review, we will report it immediately," she said at the time. "Information published that is contrary to this statement is categorically false."
Northrop Grumman said at the time that it could not comment on classified missions.