In the same year as he imagined the representation of the rhinoceros, Dürer completed engravings of the Northern and Southern celestial hemispheres. These were the first commercially printed star charts produced in Europe. While the northern constellations were fairly accurate, based on the charts of cartographer and mathematician Johnannes Stabius, and work by astronomer Conrad Heinfogel, the southern hemisphere was largely incomplete. These constellations were added towards the end of the 16th century following further European circumnavigation of the globe. This included the monoceros constellation.