Bizarre gas cloud is one of the largest structures in the Milky Way

So far it has been assumed that the largest known gas clouds in the Milky Way have a diameter of about 800 light years. Now astronomers have discovered what may be the longest structure in the Milky Way, disproving that assumption, as reported by Live Sciencet.

As a

new study confirms , this unusual cloud of hydrogen (the red-bordered area in the image) is more than 3,900 light-years long and about 150 light-years wide. The research team named the elongated cloud “Maggie”, an abbreviation for the Magdalena River – the longest river in Colombia.

The gas cloud was discovered as part of the investigation “The HI/OH/Recombination line survey often the Milky Way” (THOR), which is based on data from the radio observatory Jansky Very Large Array in New Mexico supports. It looks for objects outside of the main plane of the Milky Way, the flattened disk that contains most of the galaxy’s matter. Since Maggie is outside of this plane, the structure was much easier to see than it normally would have been.

Origin unknown

“We don’t know exactly how she got there yet,” said Jonas Syed, a PhD student at the Max Planck Institute for Astronomy (MPIA) in Germany, in a statement. “But the filament (or cloud of gas) extends about 1,600 light-years below the plane of the Milky Way.” Therefore, the radiation of the hydrogen is clearly visible without any real disturbances.

Because the With the gas cloud isolated, the researchers were able to calculate the velocity of the gas inside Maggie. They found that all of the gas was moving at the same speed and in the same direction, confirming that it was indeed a single structure and not multiple adjacent clouds.

“Maggie was already recognizable in previous analysis of the data,” said co-author Juan Soler

, an astronomer at MPIA who first spotted Maggie, in the statement. “But only the current study proves beyond a doubt that it is a coherent structure.”

Interesting composition

Hydrogen can be in

2 forms

occur. Either as H2, i.e. 2 hydrogen atoms bonded together, which is the case with most hydrogen clouds in space. Or as atomic hydrogen

Most stars form from clouds of molecular hydrogen that compress so much that they collapse under gravity. Researchers suspect that many of these clouds may have consisted of atomic hydrogen in the past. How this transformation comes about, however, remains one of the greatest remaining mysteries of star formation.

Since Maggie’s remaining 8 percent

is made up of molecular hydrogen and appears to be concentrated at certain points in the cloud, it is conjectured that it is in the process of such a transformation. The team hopes additional data from future studies will reveal more about what is happening.