We find that the very first stars in the universe were approximately one hundred times the mass of our sun and that they form within the first hundred million years after the big bang.

Using novel sophisticated computer models, we made detailed predictions about the nature of the very first luminous objects in the universe. Remarkably, new satellite data seems to suggest our purely theoretical predictions might well hold up in nature.

The paper presented results from the first calculations that followed self-consistently the formation of the very first star in the universe. It presents an advance in that for the first time one simulation could capture both cosmological as well as stellar scales. By comparison, if we would have simulated our planet earth, our smallest resolution element would have been the size of a human red blood cell. Instead we model a region as large as our galaxy and yet have resolution elements the size of our sun.

We find that the very first stars in the universe were approximately 100 times the mass of our sun and that they form within the first hundred million years after the big bang. We are making unique and detailed predictions that the next generation of telescopes will test. It is exciting since we cannot quite see these events yet and at the same time we are convinced it will not be too long until we will.

For me it began in 1994 while I was an exchange student at the University of Illinois when Mike Norman asked me, "What were the first objects in the universe?" From then on, we started building more and more elaborate computer models to answer this question. Greg Bryan, who was also a student of Mike's at Illinois, wrote this incredible computer program with which we keep resolving more aspects of the problem of primordial structure formation. Even now, after both Greg and I moved on to tenure-track faculty positions, the three of us continue to work together on these, as we think, exciting questions of the earliest events of structure formation in the universe.