An asteroid, number 6769, named Brokoff, discovered February 15, 1985 at the Kleť observatory
3276 Porta Coeli (1982 RZ1) is a Main-belt Asteroid discovered on September 15, 1982 by A. Mrkos at Klet.
The asteroid 4662 Runk was named by Czech astronomer Jana Tichá after Ferdinand Runk, as Runk had in 1830 painted a panoramic watercolor of the view from Kleť (1038 meters), the location of the Kleť Observatory.
In 1977 the south defensive tower was remodelled to the lookout tower it is today, offering a magnificent view of the surrounding area (the Písek hills with Velký Mehelník, Temelín, Vodňany, Novohrad hills, Blansko forest with the top Kleť, and hills of Šumava, Chlum, Libin, Bobik, Boubín Plechý in the background, and Brdy 50km to the north).
The asteroid 7796 Járacimrman was (re)discovered at Kleť Observatory on 16 January 1996 by Zdeněk Moravec and was designated 1996 BG.
The asteroid 3979, which was discovered by A. Mrkos in Klet on November 8, 1983, was named "Brorsen" on proposal of J. Tichá (MPC 27734 – 1996 August 28).