eso0616 — Science Release
Physics in Universe's Youth
8 May 2006: Using a quasar located 12.3 billion light-years away as a beacon, a team of astronomers detected the presence of molecular hydrogen in the farthest system ever, an otherwise invisible galaxy that we observe when the Universe was less than 1.5 billion years old, that is, about 10% of its present age. The astronomers find that there is about one hydrogen molecule for 250 hydrogen atoms. A similar set of observations for two other quasars, together with the most precise laboratory measurements, allows scientists to infer that the ratio of the proton to electron masses may have changed with time. If confirmed, this would have important consequences on our understanding of physics.