In thedawn of the universe, lThe galaxies in which stars were created contained between three and ten times more molecular gasthan their current counterparts, according to a study led by researchers from the Max Planck Institute (Germany) and published todayNature. The discovery, in which the Spanish astronomer Santiago Garcia-Burillo, from the National Astronomical Observatory, has participated, explains thehigh star creation ratein young galaxies.
Typical massive galaxies in the distant, and therefore more primitive Universe, formed stars at a much faster rate than similar galaxies today. In theory this would imply that either star formation was more efficient in the early days of the Universe, or the raw material for star formation, that is, cold molecular gas, was more abundant in those early star-forming galaxies. .
To clear up any doubts, scientists at the Max Planck Institute, led by Linda Tacconi, have taken advantage of recent improvements in the sensitivity of instruments for measuring gases in the typical galaxies where stars from two eras past were formed: when the Universe he was 24 and 40 percent of his current age. Using theinterferómetroof the Institute of Millimeter Radio Astronomy (IRAM), have shown that, at that time, the galaxies studied contained, respectively, about 44 and 34 percent cold gas, compared to between 3 and 10 percent of current spiral galaxies. The finding provides anatural explanation for today’s low rate of star formation.
