Astronomers have discovered a galaxy that's turning space gas into stars with nearly 100 percent efficiency, a rare phase of galaxy evolution that has never been observed at such extremes.

The find comes from 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, lead author of a new study, according to a statement.  

"This galaxy is like a highly tuned sports car, converting gas to stars at the most efficient rate thought to be possible," he said.

In regions of galaxies where new stars are forming, parts of gas clouds are collapsing due to gravity. When the gas is dense enough to squeeze atoms together and ignite nuclear fusion, a star is born. At the same time, winds and radiation from stars that have just formed can prevent the formation of new stars by exerting pressure on the surrounding gas, curtailing the collapse.

The find is a very interesting galaxy, with an uninteresting name -- SDSSJ1506+54 - researchers said it practically jumping out at them when they were observing it under infrared wavelengths.

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.

The research appears in the Astrophysical Journal Letters.