To see Earth from space is to be forever changed by the view. Since Alan Shepard became the first American to lay eyes on our home planet from above, countless NASA astronauts have described feeling awed by the astonishing sight and a profound shift in perspective that followed.
This unique experience is known as the overview effect – a term coined in 1987 by space philosopher and author Frank White in a book of the same name. The phenomenon creates powerful changes in the way astronauts think about Earth and life and can be particularly strong for those who lived and worked aboard the International Space Station during its 25 years of continuous human presence. The orbiting laboratory’s cupola module, equipped with seven windows looking down on Earth, provides the perfect place for observation and reflection.
As Artemis II Mission Specialist Christina Koch explained:
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“The overview effect is when you’re looking through the cupola and you see the Earth as it exists with the whole universe in the background. You see the thin blue line of the atmosphere, and then when you’re on the dark side of the Earth, you actually see this very thin green line that shows you where the atmosphere is. What you realize is every single person that you know is sustained and inside of that green line and everything else outside of it is completely inhospitable. You don’t see borders, you don’t see religious lines, you don’t see political boundaries. All you see is Earth and you see that we are way more alike than we are different.”
Koch’s Artemis II crewmate, NASA astronaut Victor Glover, said the overview effect’s potency is closely tied to the “sea level effect” – humanity’s shared experience on Earth. “You come back to sea level, and then you have a choice,” he explained. “Are you going to try to live your life a little differently? Are you going to really choose to be a member of this community of Earth?”
Many astronauts emphasize the importance of unity after experiencing the overview effect. “You see that it’s a single planet with a shared atmosphere. It’s our shared place in this universe,” said former NASA astronaut Bob Behnken. “I think that perspective, as we go through things like the pandemic or we see the challenges across our nation or across the world, we recognize that we all face them together.”
Seeing the Earth from space can also change their concept of home. Former NASA astronaut Nicole Stott recalls wanting to see her home state of Florida during her first mission to the International Space Station. “Finally, we were flying over Florida. I wanted to go to the window and see it, and then realized somewhere down the line that I wasn’t looking at Florida that same way anymore,” she said. “I still wanted to see Florida, but Florida had just become this special part of home, which is Earth. We’re all earthlings.”
For some astronauts, their perspective shift inspired them to make changes on the ground. “I think if you’re not a conservationist before you go to space, you’re at least partly a conservationist when you come back. Because when you see how thin that atmosphere is, that protective layer that we have here, you think, wow, we really have to take care of this because it does look so fragile from space,” said retired NASA astronaut Mike Foreman.
Others hope to share the overview effect with more people. “That perspective helps you grow. It has really inspired me to try to get more people this experience and to get a permanent foothold in the stars for our species,” said former NASA astronaut Jack Fischer. “I want to do everything I possibly can to help the human species, humanity as a whole, go further and grow and evolve like I know they’re capable of.”
Future crews to the orbiting laboratory can look forward to a similar experience. “In that instant, when you’re overwhelmed with that vista, when your eyes see nothing but the beauty of the Earth – every single crew member that I brought in [the cupola] for that exposure, cried,” said retired NASA astronaut T.J. Creamer. “It is heart stopping. It is soul pounding. It is breathtaking.”
For more astronaut perspectives from the International Space Station, watch “Down to Earth” on NASA+.









