Some former NASA astronauts have a message for flat-Earther B.o.B: The curve is real, and we've seen it.
Last week, the Atlanta-based rapper kicked off a crowdfunding campaign to raise $1 million, ostensibly so he can build and launch one or more satellites to settle the "question" of Earth's shape once and for all.
B.o.B doubts that Earth is round because the horizon looks pretty flat in photos taken from the planet's surface. That's a simple consequence of Earth's large size, of course, but B.o.B doesn't see it that way. "Help B.o.B find the curve!" the crowdfunding project's description reads, in part. [7 Ways to Prove the Earth Is Round Without Satellites]
This plea elicited a response from former NASA astronaut Terry Virts.
"I can save BoB a lot of money — the Earth is round. I flew around it," Virts tweeted Wednesday (Sept. 27) via his @AstroTerry account.
Apollo 11 moonwalker Buzz Aldrin (@TheRealBuzz) responded to Virts Wednesday, tweeting, "I did too. It's called an orbit: the curved path of a celestial object around a star, planet, or moon."
Retired astronaut Scott Kelly also chimed in Wednesday, posting a time-lapse video of our planet as seen from the International Space Station.
"Show you the curve? Here you go @bobatl! One full orbit around Earth. Maybe donate funds raised to #PuertoRicoRelief," Kelly (@StationCDRKelly) tweeted.
B.o.B hasn't been swayed by thousands of satellite photos, the circumnavigation of the globe, common sense or any of the other evidence showing beyond a shadow of a doubt that Earth is round, so Virts, Aldrin and Kelly are probably just shouting into the wind. But hey, it's worth a shot.
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Michael Wall is a Senior Space Writer with Space.com and joined the team in 2010. He primarily covers exoplanets, spaceflight and military space, but has been known to dabble in the space art beat. His book about the search for alien life, "Out There," was published on Nov. 13, 2018. Before becoming a science writer, Michael worked as a herpetologist and wildlife biologist. He has a Ph.D. in evolutionary biology from the University of Sydney, Australia, a bachelor's degree from the University of Arizona, and a graduate certificate in science writing from the University of California, Santa Cruz. To find out what his latest project is, you can follow Michael on Twitter.