The overview effect

Why does a trip into space leave many people changed forever?

On 7 December 1972, astronaut Harrison Schmitt looked out of the window of the Apollo 17 spacecraft as it sped away from Earth towards the Moon, and took a photo of our planet’s entire sunlit side, surrounded by inhospitable darkness. The photograph, known as the “Blue Marble”, became one of the most shared images ever. It perfectly captures just how remote and isolated our world is in space – something that’s often hard to communicate in words. Astronauts who have seen Earth from outside often come back expressing a peculiar feeling that has been given its own name – the “overview effect”.

A shift in perspective

The overview effect describes the changes in the way you understand Earth and humankind’s place on it after seeing it from afar. Some people experience a sense of interconnectedness, a realisation that we’re all made from the same space dust; others get a feeling of awe. Michael Collins, who flew aboard the first crewed mission to land on the Moon, said Earth “projected an air of fragility” when he saw it from lunar orbit. International Space Station (ISS) astronaut Nicole Stott described an overwhelming feeling of beauty. Almost every person who’s had the chance to look down on the planet has experienced their own version of the effect – but why?

Tiny planet

Seeing our home in the emptiness of space could be one of the most important lessons of any space trip. For one thing, it reveals how small Earth is – astronauts travelling to the Moon were able to block it out completely behind a raised thumb, and for any future travellers venturing deeper into the solar system, it would rapidly shrink to a pale blue dot. Yet this tiny ball of light encompasses everything we know from everyday experience – all of humanity with its triumphs and troubles, and everything else, from microbes to animals to mountain ranges.

Since 1972, nobody has been far enough from Earth to take a photograph like the Blue Marble. However, even a trip to low Earth orbit, where astronauts aboard the ISS constantly see Earth as a vast sphere below them, can be enough to trigger the overview effect. What’s more, new advances in space travel, such as the short trips to the edge of space offered by companies such as Virgin Galactic and Blue Origin, are likely to make the experience far more common – you might even get to experience it for yourself. What would it inspire you to do, try or change? Amazon founder Jeff Bezos, who rocketed to space in July, has committed around £2 billion to environmental causes after experiencing the overview effect himself.

Overview for everyone

For the moment, though, some people are working on bringing the overview effect down to Earth. Bristolbased artist Luke Jerram, for instance, has created a piece called Gaia, named after the mythical Greek goddess of the Earth. Consisting of a balloon seven metres wide with images of the surface projected onto it, it gives the viewer a chance to see Earth in 3D on a scale not usually seen by humans.

For those who are more into tech than art, a project called Spacebuzz is aiming to share the wonders of the overview effect with young people around the world using virtual reality. And NASA’S DSCOVR satellite (Deep Space Climate Observatory) delivers new Blue Marble images of Earth from a distance of almost a million miles away – you can see them for yourself at epic.gsfc.nasa.gov

Spreading and sharing the overview effect can lead us to a greater understanding that Earth is one system. Despite the conflicts that divide people, humankind is part of a complex and interconnected web of life that spans the whole world. People should try to see the big picture. So next time you gaze up at the stars, take a second to pause and think about how our own small, precious fragile world must look from out there in the dark.

Luke Jerram’s artwork.