An uncrewed Blue Origin New Glenn rocket exploded on a Florida launchpad during a test on Thursday, in a major setback for Jeff Bezos space venture as it seeks to narrow the gap with Elon Musk’s IPO-bound SpaceX.

Video posted by NASASpaceflight, which livestreams launches from Florida, showed the towering New Glenn rocket igniting on the pad at about 9pm ET (6am PKT on Friday) before erupting into a massive fireball that billowed skyward, sending a towering plume of flames and smoke into the air.

Blue Origin was preparing the rocket for its fourth launch, which was due to deliver 48 Amazon Leo satellites into low-Earth orbit, part of efforts to build a broadband constellation to rival Musks Starlink network.

Amazon Leo satellites were not integrated on the rocket at the time of the incident, a source familiar with the matter said, asking not to be named due to its sensitivity.

The explosion marks the latest setback for the long-delayed New Glenn, which is supposed to play a central role in delivering lunar landers and cargo under Nasa’s Artemis lunar exploration missions.

It comes just two days after Nasa awarded Blue Origin a $188 million contract to land rovers on the moon’s surface, and less than a week after SpaceX — years ahead in development — carried out a largely successful test of its next-generation Starship rocket.

Blue Origin confirmed it had experienced an anomaly during a hot-fire test, where a rocket engine is fired up while anchored to the ground.

“Very rough day, but we’ll rebuild whatever needs rebuilding and get back to flying. Its worth it,” Bezos said in a post on X, adding that it was too early to know the root cause.

Nasa Administrator Jared Isaacman said the agency would work with Blue Origin to support an investigation of the incident.

“Spaceflight is unforgiving, and developing new heavy-lift launch capability is extraordinarily difficult,” Isaacman said on X.

Isaacman also added that Nasa would provide information on any impacts to its Artemis and Moon Base programmes.

‘Rockets are hard’

Musk’s SpaceX and Bezos’ Blue Origin, in the latest competition between the billionaire-run companies, have been racing to help return people to the moon ahead of a planned crewed mission by China in 2030 by designing the lunar landers Nasa will use.

SpaceX, which unveiled its plans for an IPO earlier this month and is set to become the first trillion-dollar US market debut, has also faced setbacks with its rockets.

In June last year, its massive Starship spacecraft exploded in a similarly dramatic fireball during testing in Texas while preparing for a test flight.

SpaceX was partly successful in its 12th test flight of a Starship prototype last week after it deployed a clutch of mock satellites and executed a controlled splashdown of the spacecraft in the Indian Ocean.

But the Musk-owned company failed to achieve a controlled landing of the Super Heavy booster, which tumbled into the Gulf of Mexico.

Musk responded on X to a video of the Blue Origin explosion, saying, “Most unfortunate. Rockets are hard.”

Blue Origin has spent billions of dollars and roughly a decade developing New Glenn, a rocket 29-stories high with a reusable first stage meant to compete with SpaceX’s Falcon fleet and its more powerful Starship.

The US Federal Aviation Administration said it was aware of the incident, but added that it was outside its scope and did not impact air traffic in the region.