Support Aeon

‘Aeon is one of the liveliest, most wide-ranging and imaginative sources of good content on the web. A fabulous resource for the intelligent and curious.’

Professor Barry C. Smith, UK, Friend of Aeon

Aeon is a registered charity committed to the spread of knowledge and a cosmopolitan worldview.
But we can’t do it without you.

Donate now

Aeon is a registered charity committed to the spread of knowledge and a cosmopolitan worldview. Our mission is to create a sanctuary online for serious thinking.

No ads, no paywall, no clickbait – just thought-provoking ideas from the world’s leading thinkers, free to all. But we can’t do it without you.

Donate now

Paul Gilster
Writer/editor, Centauri Dreams

Paul Gilster is an American writer on aerospace and technology topics whose site, Centauri Dreams, chronicles ongoing research into interstellar flight. He is also the author of Centauri Dreams: Imagining and Planning Interstellar Exploration (2004). 

Written by Paul Gilster

Essay/
Astronomy
Distant ruins

Scientists used to scan the skies for messages from alien civilisations. Now they go looking for their ruins

Paul Gilster

Recent comments