US astronomers searching for planets outside our solar system say they have a new tool helping the quest, advanced computer models of how planets are born. Most planets form when a molecular cloud collapses into a young star with a leftover disk of gas and dust around it containing particulates that collide and coalesce over millions of years, forming larger and larger objects until a planet eventually takes shape. Researchers at the University of Texas at Austin have developed computer models to simulate these protostellar disks and the turbulence and temperatures within them that affect how and where planets form. Sally Dodson Robinson and her team at the university\'s Texas Advanced Computing Center say they\'ve found if a disk is too turbulent, the particles move too fast and bounce off each other while less turbulence means a greater chance for them to collide and stick together. With almost 2,400 candidate exoplanets awaiting confirmation, understanding the conditions that are most favorable for planet formation will aid researchers in discovering more of them and will also provide greater understanding of the evolution of Earth and our own solar system, a university release said Tuesday.