Article Posted on : - Mar 11, 2010

Artists’ representation showing outflow from a supermassive black hole inside the middle of a galaxy. A NASA/CXC/M.Weiss Photo

LONDON (BNS): A massive galaxy in the primitive Universe underwent a series of explosions so powerful that it stopped giving birth to stars, scientists have found.

The galaxy, SMM J1237+6203, located in the constellation Ursa Major, witnessed numerous blasts trillions of times more powerful than any caused by an atomic bomb.

The blasts occurred every second for millions of years, thereby halting star formation inside the galaxy, scientists at the Durham University’s Department of Physics have found and report their study in the Monthly Notices of Royal Astronomical Society.

The explosions scattered the gas needed to form new stars by helping it escape the gravitational pull of the galaxy, effectively regulating its development.

So far, it has been believed that a major event prevented star formation in massive galaxies nearer to our Milky Way in the early Universe and stopped them from expanding.

Researchers have reasoned that this could have happened due to outflow of energy blowing galaxies apart and preventing new stars from being formed, but until now, there was no evidence to prove the point.

Now, the Durham University scientists believe that huge surge of energy was caused by either the outflow of debris from the galaxy’s black hole or from powerful winds generated by dying stars exploding as supernovae.

The colossal energies generated by these outflows of energy were enough to suppress any further star formation in the galaxy.

“We are looking into the past and seeing a catastrophic event that essentially switched off star formation and halted the growth of a typical massive galaxy in the early Universe,” said Dr Dave Alexander, at the Durham University’s Department of Physics.

“Effectively the galaxy is regulating its growth by preventing new stars from being born. Theorists had predicted that huge outflows of energy were behind this activity, but it’s only now that we have seen it in action,” the scientist said.

“We believe that similar huge outflows are likely to have stopped the growth of other galaxies in the early Universe by blowing away the materials needed for star formation,” he said.

The Durham-led team now plans to study other massive forming galaxies in the early Universe to see if they too have similar traits.