Keywords: Hercules et Corona Borealis - Mercator.jpeg Hercules 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 Hercules constellation Corona Borealis Maps by Gerardus Mercator |