Mystery gas discovered near the center of Milky Way

An international team of investigators has discovered a dense, cold gas fired from the center of the Milky Way “like bullets”.

Exactly how the gas is emitted is still a mystery, but the research team, including Professor Naomi McClure-Griffiths of the Australian National University (ANU), say their findings could have important implications for the future of our galaxy.

“Galaxies can be really good at shooting themselves in the foot,” said Professor McClure-Griffiths.

“If you expel a lot of mass, you lose some material that could be used to form stars, and if you lose enough of it, the galaxy can no longer form stars.

“That, if you can see hints of the Milky Way losing this star-shaped gas, is something exciting – you wonder what happens next!”

The study also raises new questions about what is happening right now in our galactic center.

“The wind at the center of the Milky Way has been the subject of much debate since the discovery a decade ago of the so-called Fermi Bubbles – two giant orbs filled with hot gas and cosmic rays,” said Professor McClure-Griffiths.

“We have noticed that not only hot gas comes from the center of our galaxy, but also cold and very dense gas.

“This cold gas is much heavier, so moves around less easily.”

The center of the Milky Way is home to a massive black hole, but it is unclear whether this black hole displaced the gas, or whether it was blown by the thousands of massive stars in the center of the galaxy.

“We do not know how the black hole as the star formation can produce this phenomenon. We are still looking for the smoking gun, but it gets more complicated the more we learn from it,” leads author Dr. Enrico Di Teodoro of Johns Hopkins University said.

“This is the first time such a thing has been observed in our galaxy. We see this kind of process happening in other galaxies. But, with external galaxies you get much more massive black holes, star formation activity is higher, it makes it easier for the galaxy to expel material.

“And these other galaxies are obviously a long way off, we can not see them in much detail.

“Our own galaxy is almost like a lab that we can actually get into and try to understand how things work by looking closely.”

The study was published in the journal Nature.

The gas was observed with the Atacama Pathfinder EXperiment (APEX) operated by the European Southern Observatory (ESO) in Chile.