The world's most powerful rocket successfully launched from the Kennedy Space Centre in Florida on Tuesday (6 February) with an old Tesla car belonging to SpaceX CEO Musk being "driven" by a mannequin listening to David Bowie's Space Oddity on repeat.
Musk posted a photo on Twitter after the launch showing the car in space over Australia - with a spherical globe clearly seen in the background. People also responded by posting photos taken from the livestream showing the car in front of the curvature of the earth.
Musk has previously mocked the Flat Earth Society, tweeting: "Why is there no Flat Mars Society!?" after posting a beautiful photo of the red planet. The group's official Twitter account actually replied to answer his question, saying: "Hi Elon, thanks for the question. Unlike the Earth, Mars has been observed to be round."
Almost a day after the launch, the Flat Earth Society finally posted a response on Twitter responding to criticism. They wrote: "People who believe that the Earth is a globe because 'they saw a car in space on the Internet' must be the new incarnation of 'It's true, I saw it on TV!' It's a poor argument. Why would we believe any privately-held company to report the truth?"
Many people took the opportunity to use the new images as evidence to debunk the flat earth conspiracy theory, which is perpetuated by the Flat Earth Society, a community of flat-earthers whose website describes itself as "a place for freethinkers and the intellectual exchange of ideas".
Sebastian Bell posted: "Suck it Flat Earthers." However, flat-earthers did not take the mickey-taking lying down. One user replied saying: "You're a grown man and you honestly believe this is real?"
Another said: "Have you personally been to outer space? No you haven't. You're taking someone else's word for it. I'd rather believe in the Bible. I hope you realise Nasa, SpaceX, and the European Space Agency all work for Satan. Wake up and stop drinking the fluoride."
Many others also took the opportunity to point out the roundness of the earth. Twitter user Romonjo said: "Man, the Earth sure does look flat." And Kiwi drum and bass duo State of Mind's Stu Maxwell tweeted: "Tough day at the office for flat earthers..."
Reddit users also mocked flat earthers, telling them to "take that". One user suggested Musk had missed a chance to prove the earth was round once and for all: "He really should have sent a flat earther up there with him so they would shut up about flat earth."
Nonetheless, conspiracy theorists continued to claim online that the photos had been faked and photoshopped.
On its website, the Flat Earth Society explain the evidence behind its theory. "The world looks flat, the bottoms of clouds are flat, the movement of the sun; these are all examples of your senses telling you that we do not live on a spherical heliocentric world." It argues that another way of looking at the world is with scepticism, putting the burden of proof on a round world rather than a flat one.
The group does not "lend much credibility" to photographic evidence of the world being round. Reason? "It is too easily manipulated and altered. Many of the videos posted here to "prove a round earth" by showing curvature will show no curvature or even concave curvature at parts. The sources are so inaccurate it's difficult to build an argument on them in either case.
"Furthermore, barrel distortion and other quirks of modern cameras will cause a picture to distort in ways which may not be immediately obvious or apparent, especially without references within the picture. Photographs are also prone to distortion when taken through the bent glass of a pressurised cabin as well as atmospheric conditions on the outside. With this litany of problems, it's easy to see why photographic evidence is not to be trusted."
Just days earlier, flat-earther Mike Hughes failed to launch himself into the sky in a steam-powered homemade rocket at 500mph due to a mechanical glitch. He is hoping to prove with his mission that the earth is flat, by gaining enough publicity in his initial efforts to fund his ultimate project, a multi-million dollar rocket-flight where he would go up 35,000ft to see for himself and get a photographic proof.