John Glenn, who was the first American to orbit Earth, has passed away at the age of 95 in Columbus, Ohio.

Glenn was also a decorated war hero, former astronaut and senator, educator, husband, father of two, and defender of humanity who worked against the proliferation of nuclear weapons.

In the wake of the news, scientists and space luminaries have taken to Twitter with an outpouring of condolences, memories, and love.

We’ll update the list here as more space-related celebrities chime in, but below are some of the more notable tweets we’ve seen:


Paul Allen, Microsoft co-founder, philanthropist, and creator of private aerospace company Stratolaunch Systems

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Peggy Whitson, a US astronaut and the first female commander of the International Space Station

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Mae Jemison, the first woman of color in space and leader of the 100 Year Starship project

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Neil deGrasse Tyson, an astrophysicist and popularizer of science

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Jeff Bezos, the founder of Amazon and spaceflight company Blue Origin

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Scott Kelly, a US astronaut who spent more than 520 days in space

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Chris Hadfiled, a Canadian astronaut and former International Space Station commander

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Carolyn Porco, a lead scientist on NASA's Cassini mission at Saturn

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Elon Musk, PayPal co-founder and founder of SpaceX

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Bill Nye, "the science guy" and CEO of the Planetary Society

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