Astronomers have found a galaxy turning gas into stars with almost 100 percent efficiency, a rare phase of galaxy evolution that is the most extreme yet observed. The findings come from the IRAM Plateau de Bure interferometer in the French Alps, NASA's Wide-field Infrared Survey Explorer and NASA's Hubble Space Telescope.
"Galaxies burn gas like a car engine burns fuel. Most galaxies have fairly inefficient engines, meaning they form stars from their stellar fuel tanks far below the maximum theoretical rate," said Jim Geach of McGill University.
"This galaxy is like a highly tuned sports car, converting gas to stars at the most efficient rate thought to be possible," he said.
The galaxy, called SDSSJ1506+54, jumped out at the researchers when they looked at it using data from WISE's all-sky infrared survey. Infrared light is pouring out of the galaxy, equivalent to more than a thousand billion times the energy of our sun.
Hubble's visible-light observations revealed that the galaxy is extremely compact, with most of its light emanating from a region just a few hundred light-years across.
"This galaxy is forming stars at a rate hundreds of times faster than our Milky Way galaxy, but the sharp vision of Hubble revealed that the majority of the galaxy's starlight is being emitted by a region just a few percent of the diameter of the Milky Way. This is star formation at its most extreme," said Geach.