Most Environmentally-Friendly Galaxy Spotted, Converts Fuel into Stars

Astronomers have identified the greenest of galaxies with the help of NASA's Wide-field Infrared Survey Explorer (WISE), Hubble Space Telescope and the IRAM Plateau de Bure Interferometer in the French Alps.

According to the astronomers, the galaxy converts fuel into stars with almost 100 percent efficiency. Located some 6 billion light years from Earth, this may be the most environmentally-friendly galaxy ever spotted. This discovery was revealed by NASA a day after the world celebrated Earth Day i.e., April 22. Dubbed as SDSSJ1506+54, this distant galaxy is the greenest galaxy till date.

"This galaxy is remarkably efficient," said Jim Geach of McGill University in Canada, lead author of the new study. "It's converting its gas supply into new stars at the maximum rate thought possible."

A typical galaxy like the Milky Way uses just a part of the complete gas supply to form stars, with a bulk of fuel being dormant; whereas SDSSJ1506+54 quickly consumes all the gas for star formation. The gas is spread widely throughout the galaxy, with a lot of recent stars being formed within separate dense knots in the spiral arms. In the case of SDSSJ1506+54, the gas is located in the central core where it has been ignited in a strong burst of star formation.

According to Geach, the scientists are witnessing a very rare phase of evolution which is not only extreme but also very efficient.

Based on the Hubble's visible light observation, the astronomers state that the galaxy is extremely compact. On measuring the gas in the galaxy with IRAM Plateau de Bure Interferometer, they detected the millimeter wave light emitted from carbon monoxide, which gives clues to the presence of the gas hydrogen, a fuel for stars.  

"We see some gas outflowing from this galaxy at millions of miles per hour, and this gas may have been blown away by the powerful radiation from the newly formed stars," said Ryan Hickox, an astrophysicist at Dartmouth College, Hanover, N.H., and a co-author on the study.

This is a normal galaxy that is trapped in a short-lived phase of evolution. They state that in tens of millions of years, SDSSJ1506+54 will use up most of the gas and convert into an elliptical galaxy.