Elon Musk is publicly brawling with the Trump administration again — this time with Transportation Secretary and acting NASA Administrator Sean Duffy.
The big picture: Musk's criticisms came as Duffy suggested this week that Musk's SpaceX was behind on its obligations to send U.S. astronauts to the moon.
Driving the news: Musk on Tuesday addressed a Wall Street Journal story reporting that Duffy is pushing for NASA to be folded into the Transportation Department.
- Musk used X, which he owns, to slam Duffy repeatedly, calling him "Sean Dummy" and saying that he "is trying to kill NASA!"
Catch up quick: Duffy told CNBC on Monday that SpaceX was "behind" schedule on its project to return the U.S. to the moon, adding that he would consider contracts with competitors like Jeff Bezos' Blue Origin.
- "We're not going to wait for one company," Duffy said on CNBC's "Squawk Box." "We're going to push this forward and win the second space race against the Chinese. Get back to the moon, set up a camp, a base."
- Musk has previously clashed with Duffy over Musk's DOGE cuts to the Federal Aviation Administration, The New York Times reported in March.
What they're saying: "The person responsible for America's space program can't have a 2 digit IQ," Musk wrote in another Tuesday post, responding to one user who said "We need someone else besides Duffy."
- Musk then posted a poll asking users: "Should someone whose biggest claim to fame is climbing trees be running America's space program?" likely alluding to Duffy's background as a competitive speed climber.
Duffy did not address Musk's aspersions directly, but on Tuesday afternoon responded to his Monday comments about the acting NASA chief "opening up" more production to Blue Origin and other companies.
- "It seems silly to imagine someone getting us there faster than SpaceX," one user responded to Duffy's announcement on X.
- In response, Musk said,"They won't. SpaceX is moving like lightning compared to the rest of the space industry."
Zoom in: Duffy's reply a day later: "Love the passion. The race to the Moon is ON. Great companies shouldn't be afraid of a challenge."
- When approached for comment on Musk's insults, NASA spokesperson Bethany Stevens directed Axios to Duffy's post.
- On Tuesday, Musk also reshared another user's post defending Jared Isaacman, whose nomination to lead NASA was pulled in May.
- The user said that "lobbying against Jared Isaacman, literally the most qualified and best person to be the new head of NASA, is so dumb."
Context: Isaacman, a fintech billionaire, is a close associate of Musk's, and suggested at the time that Trump pulled the nomination as part of an effort to distance himself with the former DOGE head.
Flashback: SpaceX had beat out Blue Origin for the NASA contract in 2021, though Bezos' company is also developing technology for the program.
- SpaceX and Blue Origin will have until Oct. 29 to offer ways to speed up the project, a NASA official told CNBC.
The project has had multiple setbacks so far.
- In January, the agency delayed its planned Artemis missions.
- NASA's first Artemis launch with astronauts is now scheduled for 2026, with another trip moved to 2027.
The intrigue: President Trump and Musk have mostly struck a civil tone following their own public falling out in June, but that hasn't stopped Musk from criticizing other members of the administration he was once part of.
Editor's note: This article has been updated with comment from acting NASA Administrator Sean Duffy and further context.
