Scientists find themselves perplexed after discovering dust and gas discs at the center of the Milky Way galaxy. Theory states that the existence of the discs is impossible.
This particular region of space is known for its star formation activity, which means that there's a lot of UV radiation present. This sort of radiation usually destroys such dust discs, but for some reason, those detected in the center of the Milky Way are still going strong.
The heart of the Milky Way is a virtual nursery for baby stars. It is here that more stars are born than anywhere else in the galaxy. Star clusters form, including the "Quintuplet" and "Arches" clusters, which is the particular region of space an international team of astronomers recently studied using the European Space Agency's Very Large Telescope (VLT) in Chile. This cluster contains young stars with masses up to 100 times that of the sun. It is there where researchers discovered the impossible 20 dust and gas discs.
"We expected that the enormous radiative energy of these giant beasts [would] evaporate the material around their smaller neighbours in less than one million years," says Dr. Andrea Stolte of the Argelander Institute for Astronomy at the University of Bonn.
This obviously surprised scientists because they did not expect to find any such discs after a few hundred thousand years. However, they found 20, contradicting current theories about how discs evaporate in regions of space when exposed to the destructive UV radiation of new stars.
So how did these discs survive such radiation? Well, that's still anyone's guess. Scientists, of course, though, have a few possible explanations. One is that the discs are more resilient to hostile environments than initially thought. Another explanation, though, is that there's something else happening that protects these discs from evaporating. It's even likely that the protection comes from companion stars: this happens when two stars orbit each other and the bigger star provides energy to the smaller one. This transfer could consistently replace nearby disc material being lost due to evaporation.
"Many unknown processes take place in these rich, young star clusters," says Stolte. "The tight interaction and mass flow between numerous close twins observed in other star-forming environments might also be the explanation for the dusty discs we found in these massive clusters."
There's even a possibility that because these discs can survive such extreme regions for such long periods of time, they could be proving grounds for planet formation. The discovery was published in the journal Astronomy & Astrophysics.
