Keywords: Boötes et Corona Borealis - Mercator.jpeg Boötes and Corona Borealis constellations from the Mercator celestial globe The Mercator Globes at Harvard Map Collection http //hcl harvard edu/mercatorglobes/ 1551 Gerard Mercator 1512-1594 PD-old-100 Mercator celestial globe Boötes Corona Australis Maps by Gerardus Mercator |