Elon Musk taunts President Biden with 'sleeping' tweet after SpaceX completes mission

Business mogul and CEO Elon Musk took a jab at President Joe Biden on Sunday, the day after his private spaceflight, SpaceX, completed a historic mission as the first all-civilian flight crew.

Musk responded on Twitter to a user who asked about Biden. The follower commented: "The President of the United States has refused to even acknowledge the 4 newest American astronauts who helped raise hundreds of millions of dollars for St. Jude. What's your theory on why that is?"

Musk's short response was hardly subtle. "He's still sleeping," he tweeted back.

The lack of support from Biden came after NASA officials and even Musk's rival Jeff Bezos all congratulated SpaceX, which safely returned its Crew Dragon spacecraft from orbit on Saturday. It was carrying four members of the Inspiration4 mission – the first-ever non-professional astronaut crew – back to Earth after spending three days in space.

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Musk helped raise more than $200 million for St. Jude Children's Research Hospital with the effort. With the all-civilian crew, the mission also featured the first Black woman to serve as a spacecraft pilot, the youngest American to become an astronaut to date, and the first person to fly in space with a prosthesis.

Musk's "still sleeping" mock of Biden mirrors taunts made by former President Donald Trump, who often called Biden "sleepy Joe" during the 2020 presidential campaign. The Tesla CEO has pledged in the past to "stay out of politics" and SpaceX has kept a strong relationship with the federal government, having recently won a $2.89 billion contract to build NASA's next crewed lunar lander.

Prior to Biden taking office, however, SpaceX went under investigation by the Department of Justice following accusations of discrimination against job applicants based on citizenship status.

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This article originally appeared on USA TODAY: Elon Musk taunts Biden over SpaceX mission with 'sleeping' tweet