Gotha Observatory, Astronomical observatory in Gotha, Germany.

Gotha Observatory was an observatory facility with five sections on Seeberg hill, featuring a central rotating dome and two wings for staff accommodation. It was equipped with several instruments including an eighteen-inch quadrant, transit instruments, Hadley sextants, and a Gregorian reflector for astronomical measurement.

Duke Ernest II initiated the observatory and secured Franz Xaver von Zach as first director in 1786; Zach arrived in Gotha that June as court astronomer. The Seeberg observatory, built to Zach's plan, opened in 1790 and served until 1839. Ernest II died in 1804, and in 1806 the instruments were returned to Gotha and stored in Friedenstein Castle.

The location became known as a center where scientists from many countries gathered to share their work and observations. This made it an important place for European astronomers to connect and advance their field together.

The observatory consisted of several sites in Gotha, including the building on Jägerstraße whose street façade is shown in photographs. The Seeberg observatory on the Kleinen Seeberg was a massive east-west building with a central rotating dome and two perpendicular wings. The tower was dismantled in 1810 and the side buildings in 1811.

Duke Ernst II spent 38,000 thalers of his own apanage on building the Seeberg observatory and 20,000 more on its instruments. His will made the observatory the only visible monument of his life, and he set aside 40,000 thalers whose 4 percent interest was to pay for upkeep and the astronomer's salary.