Lear 21 at English Wikipedia [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons
Venus vom Hohle Fels
By Thilo Parg [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)], from Wikimedia Commons
Nelson Mandela
South Africa The Good News / www.sagoodnews.co.za [CC BY 2.0 (https://creativecommons.org/licenses/by/2.0)], via Wikimedia Commons
Loewenmensch
By Dagmar Hollmann [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)], from Wikimedia Commons
Pluto
By NASA/JHUAPL/SwRI [Public domain], via Wikimedia Commons
Villa Esche
By Michael Sander [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)], from Wikimedia Commons
Space Shuttle Atlantis
By Bill Ingalls [Public domain], via Wikimedia Commons
Denkmal für die ermordeten Juden Europas
By K. Weisser [CC BY-SA 2.0 de (https://creativecommons.org/licenses/by-sa/2.0/de/deed.en)], from Wikimedia Commons
Dolly – das Schaf
From English Wikipedia: https://en.wikipedia.org/wiki/Image:Dollyscotland.JPG
Edward Snowden
Laura Poitras / Praxis Films [CC BY 3.0 (https://creativecommons.org/licenses/by/3.0)], via Wikimedia Commons
Der letzte Trabant
Bundesarchiv, Bild 183-P0619-306 / Ludwig, Jürgen / CC-BY-SA 3.0 [CC BY-SA 3.0 de (https://creativecommons.org/licenses/by-sa/3.0/de/deed.en)], via Wikimedia Commons
Die Himmelsscheibe von Nebra
Dbachmann [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0/)], via Wikimedia Commons