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.
Bituminous coal or black coal is a relatively soft coal containing a tarlike substance called bitumen. It is of higher quality than lignite coal but of poorer quality than anthracite. Formation is usually the result of high pressure being exerted on lignite. Its coloration can be black or sometimes dark brown; often there are well-defined bands of bright and dull material within the seams.