1. Astronomers have found a moon size diamond that formed at the center of a white dwarf star,a dead core of a burned out star, called as bpm 37093.
2. Astronomer have also found a Jupiter size planet which orbit a pair of star.in which one of the star is a white dwarf, this system is found in a densely populated star region which contain 100,000 star.
3. Astronomer have discover a planet which orbit a pulsar star. pulsar star called as psr 1257+12 is a solid star which formed at the center of a exploding star,which emit powerfull x ray radiation many times hotter than our sun. mark kuchener an astronomer mentioned this planet as a best example for diamond planets to sum up... at the center of a dead star a planet size diamond crystal have been formed and a dead star also found near a star.and diamond planets as mentioned by expert found orbit a highly radiating star. therefore it's become clear that planets are formed at the center of dead star and when they catched by a nearest star the gas which envelope the centrally formed planet evaporated by the new star and finally orbit the new star as a planet.