# Earth Is the Cradle of Humanity but One Cannot Live in a Cradle Forever by Konstantin Tsiolkovsky > "Earth is the cradle of humanity, but one cannot live in a cradle forever." > **— Konstantin Tsiolkovsky**, *1911, Letter / spaceflight maxim* ## Sources and Context - **Direct or authoritative source:** [Letter / spaceflight maxim](https://www.nasa.gov/history/space-station-20th-historical-origins-of-iss/) — the linked page contains the quoted wording and supports the recorded attribution and occasion. ## Related Articles and Collections - **Collection:** [[collections/Simple Reminders|Simple Reminders]] - **Collection:** [[collections/MARS|MARS]] - **Article:** [[articles/We Were Never Going to Make It|We Were Never Going to Make It]] - **Article:** [[articles/The Last Migration Will Not Be Human|The Last Migration Will Not Be Human]] ## Related Topics - [[wiki/Konstantin Tsiolkovsky|Konstantin Tsiolkovsky]] ## Share on Social Media ``` "Earth is the cradle of humanity, but one cannot live in a cradle forever." — Konstantin Tsiolkovsky, 1911, Letter / spaceflight maxim https://bryantmcgill.com/simple-reminders-konstantin-tsiolkovsky-earth-cradle-humanity-cannot-live ```