Outflows from twelve merging galaxies

The twelve galaxies in these NASA/ESA Hubble Space Telescope images are undergoing a firestorm of star birth, as shown by their bright white cores.

Hubble reveals that the galaxies' star-making frenzy was ignited by mergers with other galaxies. The odd shapes of many of the galaxies are telltale evidence of those close encounters.

The new Hubble Wide Field Camera 3 observations suggest that energy from the star-birthing frenzy created powerful winds that are blowing out the gas, meaning it is not available to form future generations of stars.

This activity occurred when the Universe was half its current age of 13.7 billion years. The gas-poor galaxies may eventually become so-called red and dead galaxies, composed only of aging stars.

The galaxies are the most compact yet found. They contain as much mass as our Milky Way galaxy, but packed into a much smaller area. The smallest galaxies are about 650 light-years across, one-sixtieth the width of our Milky Way galaxy.

The Hubble false-colour images were processed to bring out important details in the galaxies. The images were taken in 2010.