He’s “trying to kill NASA!”

space x and tesla CEO Elon Musk spoke to the media this week to criticize acting NASA administrator Sean Duffy after he said the billionaire space company was lagging behind the US’ plan to return to the moon.

“The head of America’s space program cannot have a double-digit IQ,” Musk wrote in a post to X on Tuesday.

In response to other users’ posts, Musk called the Secretary of Transportation a “Sean dummy” and said he was “trying to kill NASA!” Musk later posted a poll asking users, “Should someone whose biggest claim to fame is climbing trees lead America’s space program?” Musk appears to be referring to Duffy’s background as a competitive speed climber.

On Monday, Duffy told CNBC that SpaceX is “behind schedule” in building a lunar landing system for the space agency’s Artemis III mission, and said it would consider other deals with competitors such as Jeff Bezos’ Blue Origin.

NASA officials told CNBC that SpaceX and Blue Origin need to present a way to accelerate the project by Oct. 29. The agency will also ask industry to suggest ways to “increase the frequency” of moon missions.

President Donald Trump selected Duffy to be NASA’s acting administrator in July. The position had remained vacant since President Trump took office. Trump had previously nominated Musk’s ally Jared Isaacman, but withdrew his nomination earlier this year, citing Musk as a “blue-blooded Democrat who has never served the Republican Party.”

CNBC reported earlier this month that President Trump met with Isaacman to reconsider his role.

NASA is racing with China and others to return humans to the moon for the first time since 1972. NASA launched the Artemis program during the Trump administration with the goal of establishing a “long-term presence” on the moon for scientific and technological discoveries.

SpaceX was awarded a contract to build the technology in 2021. other contractors such as Blue Origin; lockheed martin and boeing Participating in various stages of the program.

However, the project was not without setbacks.

NASA launched the first Artemis mission in November 2022. Last December, NASA postponed its planned Artemis mission. NASA’s first Artemis launch with astronauts is currently scheduled for April 2026, and a third mission to land two astronauts on the moon is planned for 2027.

The space agency is also currently dealing with aftershocks from the ongoing government shutdown, which threatens to stall plans to restart contracts. CNBC previously reported that NASA employees are working on the mission with contractors and will remain at work during the shutdown.

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