Star formation. Image 4 of 6. Computer model of the 0.08 light year (ly) wide core of a 1.2ly wide gas ball 246,000 years after it began collapsing, a process that causes star formation. The ball holds 50 solar masses of gas and collapses under its own gravity. Brighter areas are denser. New stars (white) and a dense gas disc (lower centre) are seen. This model used 100,000 processing hours on a supercomputer at the United Kingdom Astro- physical Fluid Facility (UKAFF) at Leicester University, UK. It will increase understanding of the star formation process, and the likelihood of planetary system formation. For a sequence lasting 266,000 years, see images R590/089-094.