Astronomers have spotted a teenage galaxy going through an incredible growth spurt, creating new stars 100 times faster than our staid old Milky Way.
This busy galaxy is in the distant universe, so its light has taken eons to reach Earth. Scientists are seeing it as it would have appeared about 10 billion years ago just three billion years after the Big Bang.
Baby stars aren't forming uniformly throughout the galaxy, called SMM J2135-0102. Instead, star formation appears to be concentrated in four main areas each about 100 times brighter than any star-forming regions in the Milky Way. This galaxy is birthing about 250 sun-like stars a year.
The new discovery adds to growing evidence that many young galaxies went through periods of vigorous star creation in the early universe, a sort of cosmic puberty, the researchers say.
"We don't fully understand why the stars are forming so rapidly but our results suggest that stars formed much more efficiently in the early universe than they do today," said lead researcher Mark Swinbank of the Institute for Computational Cosmology at Durham University in England. "Galaxies in the early universe appear to have gone through rapid growth and stars like our sun formed much more quickly than they do today."
The researchers observed SMM J2135-0102 with the Atacama Pathfinder Experiment (APEX) telescope, which is operated in Chile by the European Southern Observatory (ESO).
The researchers hope to compare this galaxy with nearby galaxies to learn more about how star formation was different in the young universe.
"The star formation in this galaxy's large dust clouds is unlike that in the nearby universe," said co-researcher Carlos De Breuck of ESO. "However, our observations suggest that we should be able to use underlying physics from the densest cores in nearby galaxies to understand star birth in these more distant galaxies."
The study is detailed in the March 21 issue of the journal Nature. The research was funded by the Royal Astronomical Society and the Science and Technology Facilities Council in the U.K.