The establishment of the festival was initiated by President VÃ¡clav Havel, who opened Prague Castle to artists at the beginning of the 1990s in order to attract the public. The first performance of Shakespeare took place here in 1990 and the festival has been held here regularly since 1998.
1 A black dwarf is a white dwarf that has cooled sufficiently such that it no longer emits any visible light. 2  A brown dwarf is a substellar object not massive enough to ever fuse hydrogen into helium, but still massive enough to fuse deuterium âless than about 0.08 solar masses and more than about 13 Jupiter masses.
by Jean Tate on September 23, 2009. A black dwarf is a white dwarf that has cooled down to the temperature of the cosmic microwave background, and so is invisible. Unlike red dwarfs, brown dwarfs, and white dwarfs, black dwarfs are entirely hypothetical.Not a black dwarf ...yet (white dwarf Sirius B).Once a star has evolved to become a white dwarf, it no longer has an internal source of heat, and is shining only because it is still hot.nlike red dwarfs, brown dwarfs, and white dwarfs, black dwarfs are entirely hypothetical. Not a black dwarf ... yet (white dwarf Sirius B). Once a star has evolved to become a white dwarf, it no longer has an internal source of heat, and is shining only because it is still hot.