Cygnus X-1 is one of the most famous X-ray binaries in our Galaxy. This system consists of a massive blue supergiant and an invisible companion
Category: Perek-2m

During our tours of the Ondřejov Observatory we always tell you that once every few years the main mirror of the largest Czech telescope is

Astronomers from Astronomical Institute (AI) in Ondřejov studied the red dwarf star AD Leonis, which is known for its significant flaring activity. They coordinated the